Pešák was born in 1944 in the town of Jaroměř, then part of the Protectorate of Bohemia and Moravia.

[citation needed] In 1972, he graduated from the Prague Conservatory and then worked for three years in the Central Bohemian Symphony Orchestra in Poděbrady as a clarinetist.

[4] He is best known for his work with Ivan Mládek, in the latter's Banjo Band, and particularly for his high-spirited performance in the 1977 video for the song "Jožin z bažin".

[5] In Pešák's later years, he sang with Václav Upír Krejčí in a vocal duo named Dýza Boys, and he appeared in a number of films, including Trhala fialky dynamitem (1992), as well as television series.

[6] Pešák had his own band, a rock and roll revival group named Rockec Ivo Pešáka.