Petrus Antonius "Peter" Lankhorst (born 1 January 1947) is a retired Dutch politician of the GreenLeft (GL) party and political consultant.

Petrus Antonius Lankhorst was born on 1 January 1947 in Zwolle in the Netherlands Province of Overijssel in a Roman Catholic family.

Lankhorst joined the Political Party of Radicals and entered the Amsterdam city council.

He was spokesperson on housing, education, Transport, Public Works and Water Management and youth welfare.

In 1989 Lankhorst initiated a law to oblige high schools to promulgate a statute which lays down the rights of students.