Hendrik Nikolaas Theodoor Simons, known as Heintje, (born August 12, 1955 in Kerkrade-Bleijerheide, Netherlands) is a Dutch singer and actor.
He became particularly famous as a child singer with his hit song Mama in 1967 and as a child actor with his appearances in numerous German movies in the 1960s and 1970s. He currently lives in Neu-Moresnet a part of the city of Kelmis in the Belgian province of Liège. Heintje continued to sing as an adult as Hein Simons and is particularly popular in German speaking countries.