Van Straaten was born in Arnhem in the Netherlands on 25 March 1935. His elder brother Gerard also became a well-known illustrator. Van Straaten studied at the Gerrit Rietveld Academie in Amsterdam and started his career on 26 July 1958 for the Dutch newspaper Het Parool, where he illustrated news reports. Later he also drew political cartoons. From 1968 to 1987 he published a daily comic strip, Vader & Zoon (Father and Son), which became a huge success and inspired a television series.

Van Straaten is best known for his gag cartoons based on observational comedy. His series Dagelijks Leven (Daily Life) depicts people in amusing recognizable everyday situations. The series Doe ik 't goed? (Am I doing well?) centered on gags about people having sex and men usually having trouble satisfying their female partners. Between 1984 and 2000 he drew a weekly comic strip about a single woman called Agnes. His work was featured in comic books and a yearly calendar, Peter's Zeurkalender (Peter's Nagging Calendar, a pun on the word zeuren (to nag) and scheurkalender (a calendar where one can rip off one page a day to read a joke)). Van Straaten's cartoons have been published in Het Parool, Humo, Penthouse and Vrij Nederland.