Immers joined the Rotterdam club from ADO Den Haag in July 2012 and has established himself as a regular with the 14-time Eredivisie champions.
The 27-year-old enjoyed an impressive season in 2013-14, scoring 12 goals in 37 appearances as Feyenoord finished second behind fierce rivals Ajax in the Dutch top flight, ensuring a place in the UEFA Champions League.
Immers' deal was due to expire in 2016, but Feyenoord have now secured his services for another year.
"At the time I switched to Feyenoord, I needed some time to get used to it," Immers told the club's official website. "After a difficult start things began to get better.
"From the beginning I played pretty much every match and I felt the growing appreciation of the public.
"The support of the fans is fantastic, especially in this respect Feyenoord is the biggest club in the Netherlands in my opinion.
"I'm really enjoying myself and I feel completely at home at Feyenoord. For me that was one of the conditions for staying here longer."
