There are multiple artists with this name:

1) Lena Meyer-Landrut (bo… Read Full Bio ↴There are multiple artists with this name:

1) Lena Meyer-Landrut (born 23 May 1991), also known by her stage name Lena, is a German singer. She represented Germany in the Eurovision Song Contest 2010 in Oslo, Norway, and won the contest with the song Satellite which also became #1 in European charts.

2) Lena is a French dubby techno project by Mathias Delplanque.

3) Lena, aka Lena Griffin, is a multi-instrumentalist and ambient musician based in Portland, Oregon, United States. She is the wife of ambient experimentalist M. Griffin, and works as the full-time manager of Hypnos Recordings.

4) Lena, aka Lena Burke and Lena Pérez, is a Cuban pianist, composer and singer.

5) Lena is an Italian musical project produced by Roberto Zanetti. "Run to Me" is the only song recorded by the artist.

6) Lena was a Swedish industrial / noise project active in the mid-1980s.

7) Lena is an Albanian Singer.

8) Lena (레나) , aka Kang Lena (강레나) is a South Korean singer, member of girl group GWSN.

Detailed biographies:

1) Lena Meyer-Landrut (born 23 May 1991), also known by her stage name Lena, is a German singer. She represented Germany in the Eurovision Song Contest 2010 in Oslo, Norway, and won the contest with the song Satellite. With her three entries from the German national final Unser Star für Oslo (Our Star for Oslo), Meyer-Landrut set an all-time chart record in her home country by debuting with three songs in the top five of the German singles chart. Satellite debuted at number one in Germany, and has since been certified 5x Gold. In May 2010, Meyer-Landrut released her first album, My Cassette Player, which debuted at number one in the German albums chart.
Despite having had no professional singing experience, Meyer-Landrut decided to participate in the talent show Unser Star für Oslo (Our Star for Oslo), a newly-created national television programme to select the German entry for the Eurovision Song Contest 2010 in Oslo. Among 4,500 entrants, Meyer-Landrut was picked as one of the 20 contestants for the show. Asked about her motivation to apply, she stated, "I like to test myself. I wanted to see how I am perceived, and I wanted to hear what people with knowledge have to say about it. I personally can’t judge myself at all." After her first appearance, performing My Same by British singer Adele, Meyer-Landrut received much praise from the show's jury panel and was instantly considered the favourite. The following week, Adele's My Same entered the German singles chart at number 61. Meyer-Landrut reached the final of Unser Star für Oslo, mainly performing lesser known songs of international artists such as The Bird and the Bee, Kate Nash, Paolo Nutini and Lisa Mitchell. Out of her eight cover performances, five of the original songs subsequently charted in Germany, with all but one reaching their peak chart position. While competing at Unser Star für Oslo, Meyer-Landrut continued to attend school. The last show was held one month before the start of her final exams. Throughout the show, Meyer-Landrut was seen as the clear favourite, often leading internet polls by huge margins. In the final on 12 March 2010, Meyer-Landrut sang three songs specifically written for the contest, Bee, Satellite and Love Me . Through televoting, the audience chose "Satellite", written by American Julie Frost and Dane John Gordon, as Lena's designated song in the event of her victory. In a second round of voting, Meyer-Landrut was chosen as Germany's entry for the 55th Eurovision Song Contest, beating the last remaining contestant, Jennifer Braun. The music video for "Satellite" was shot during the night of the final and premiered on German television stations four days later.
One day after winning Unser Star für Oslo, all three of the songs performed by her in the final topped the German iTunes chart, making her the first singer to achieve such a feat. Her three songs all entered the top five of the German singles chart, reaching positions number one, three and four, which no artist had ever achieved since charts were first released in Germany in 1959. "Satellite" sold over 100,000 downloads in its first week and was eligible to be certified gold, becoming Germany's fastest selling digital release ever. It was certified platinum in its fourth week, remaining at number one for five consecutive weeks in Germany. It peaked at number two in both Austria and Switzerland.
On 7 May 2010, Lena released her debut album, My Cassette Player. Produced by Stefan Raab, it includes the singles "Satellite", "Love Me" and "Bee", as well as two cover songs and eight previously-unreleased songs. Meyer-Landrut is credited as a co-writer on five songs. The album debuted at number one in the German albums chart, number three in both the Austrian and the Swiss albums chart and number five in Billboard's European Top 100 Albums.
The final of the Eurovision Song Contest was held on 29 May 2010 at Oslo's Telenor Arena. Lena won the contest with the song "Satellite", giving Germany its first win since 1982, and its first as a unified country. She returned to Hanover the following day, where she was greeted by 40,000 people. In June, "Satellite" regained the top spot in the German singles chart for one week and also peaked at number one in Denmark, Finland, Norway, Sweden and Switzerland. It also topped European Hot 100 singles chart, being the first Eurovision song to achieve this.
Meyer-Landrut attempted to defend her title in the 2011 Eurovision Song Contest. She was the third winner to do so, and the first in over 50 years.
In January 2011, the TV-Show "Unser Song für Deutschland" was announced. The viewers of the show decided for Meyer-Landrut's 2011 Eurovision song. All twelve songs Meyer-Landrut performed during that show were recorded on her second studio album Good News which was released on 8 February 2011. The album debuted at number one of german album charts and managed to reach a Gold status for selling more than 100,000 units in Germany in its first week of release.
On February 18, the "Unser Song für Deutschland" final was held and it was decided through televoting that Meyer-Landrut would perform the entry "Taken by a Stranger" in the final of the Eurovision Song Contest 2011 where it was placed tenth. The song was released at 22 February 2011.
In April 2011 she went on her first German tour in the largest concert halls in Berlin, Hanover, Frankfurt, Dortmund, Leipzig, Hamburg, Munich, Stuttgart and Cologne. The concert in Frankfurt was recorded on video and was released on DVD in May 2011.
She also sang the theme song to the German movie What a Man. In 2012 the single Stardust was released on September 21. In December it was certified Gold for selling 150,000 copies. The album Stardust was released on 12 October and it debuted at #2 on German Albums chart. Since October 2012 she performed the theme song in the opening credits of the Sesamstraße, the German version of the Sesame Street. In November 2012 she covered the Pippi Longstocking song Sjörövar Fabbe (Seeräuber-Opa Fabian) for the compilation album Giraffenaffen.
Lena's sixth single Neon was released on March 15. 2013 In October 2013 a song called Revolution a collaboration with Dicks on Fire was released.
Following her success in Germany, Meyer-Landrut has said she would enjoy a singing or an acting career, but explained, "I'm not fixated on doing music my whole life." She stated she originally planned to study acting after graduating school, but now is unsure "if time allows". She has said her musical influences include Adele, Kate Nash, Vanessa Carlton, as well as the German singer Clueso and German pop rock band Wir sind Helden.

2) Lena is a dubby techno project from France, formed by electronic composer Mathias Delplanque. He debuted in 2002 with the album "Lane" and the latest record (from 2010) is titled "Circonstances / Variations 1-4".

Discography:
Lena : Circonstances / Variations 1-4 (Bruit Clair / Sounds Around 2010)
Lena & The Floating Roots Orchestra : Lost-Wax (Plush, 2008)
Lena : The Uncertain Trail (Sounds Around, 2007)
Lena : Floating Roots (Quatermass Recordings, 2004)
Lena : Lane (Quatermass Recordings, 2002)

http://www.bruitclair.com
http://www.mathiasdelplanque.com
http://www.myspace.com/lenafloatingdub

3) Lena Griffin is a multi-instrumentalist and ambient musician based in Portland, Oregon, United States. She is the wife of ambient experimentalist M. Griffin, and works as the full-time manager of Hypnos Recordings. Her debut album, "Extended Gestures for Cello", was released on Hypnos Secret Sounds in 2007. As indicated by the album's title, these recordings are entirely made up of solo cello, performed live in studio by Lena, with electronic treatments and production by M. Griffin. The resultant sound is somewhere between recognizably cello-like traditional playing, and an edgier, more atmospheric, and more challenging tone.