Karim expressed his acting skill developed through his early work in the school theater. In 1986 Karim joined the theater troupe "Nattokendro" and worked for 15 years.After over a decade in theater, Karim emerged on the small screen in 1999, with the single-episode TV play Atithi, directed by Ferdous Hasan and aired on Channel I.
2004 he played two important roles in two different TV works. One of those roles included the popular telefilm Kyarom, where he performed with co-artist Nusrat Imroz Tisha. In 2009, he acted in his first film Third Person Singular Number, with co-artist Tisha. He acted in his first Drama serial 420 aired on Channel I. After this, he worked in the two drama serials, Vober Hat and Ghor Kutum. Karim also acted with Bengali film Daruchini Dip directed by Toukir Ahmed. More:-https://en.wikipedia.org/wiki/Mosharraf_Karim