Jiří Petráček was born in Prague, and graduated from the Hollarka art school in 1959. He has worked as a freelance artist from 1971 until his retirement in 2002. His first comic book work was 'Expedice Yeti' in 1971, and was signed Peta Dudwolla (a joint signature for the authors Petracek, Oldrich Dud and Otakar Vol). He has also illustrated several educational textbooks, especially about Czech history.
He was a contributor to Sedmicka pionyru from 1979, where he created the comic series 'Trináctka ze Staré Ctvrti' ('Thirteen of the old Quarter') with Pavel Toufar from 1981 to 1984. He was subsequently a contributor to ABC with 'Guliver', 'Golem', 'Návratu z ráje', 'Nebe v plamenech', 'Divokého Dicka' and 'Pána jaguárů' until 1997, all in cooperation with either Ruda Baudis or Vašek Šorel.
He additionally made 'Clovek zvaný Son' with Ivo Pehchar and 'Kamarádi z prérie' with Pavel Kosatík and Magda Ziková for the Knizní Podnikatelský Klub (Business Book Club) in 1990 and 1991. Petracek and Pechar also worked together on six mini-comics in the 'Stopar' ('Hitchhiker') series for Pressfoto. Following the Velvet Revolution in 1989, Petracek was also present in Kometa magazine.