Jānis Apeinis made his debut at the Latvian National Opera in 2003. He made his debut in the title role of Tchaikovsky's Eugene Onegin at the Tiroler Landestheater in 2008 and returned to the Tiroler Landestheater with the role of Carlo Gerard in Giordano's Andrea Chenier (2010).
His roles include Oniegin (Eugene Oniegin), Escamillo (Carmen), Figaro (Il Barbiere di Siviglia), Count Luna (Il Trovatore), Lescaut (Manon Lescaut), Count Almaviva (Le Nozze di Figaro), Enrico Ashton (Luci adi Lammermoor), Don Giovani (Dons Giovani), Scarpia (Tosca), Marcello (La Boheme), Sharpless (madama Butterfly) and others.
He can be heard at the Mikhailovsky Theatre (St. Petersburg, Russia) as Onegin. In 2013 this performance was awarded with the National Theater Award Golden Mask in categories ‘’Best Opera Production’’ and ‘’Best Opera Director’’.
Laureate of the annual Latvijas Gāze Award as the Best Opera Soloist of the Year (2008, 2011, 2012). His roles include Yeletsky (Tchaikovsky's The Queen of Spades), Escamillo (Bizet's Carmen), Sharpless (Puccini's Madama Butterfly), Marcello (Puccini's La Bohème), and Joseph (Ešenvalds's Joseph Is A Fruitful Bough) among others.