Gerrit Jan van Eijken (Amersfoort, 5 May 1832 - Dalston, London, 22 March 1879) was a Dutch composer.
He studied first under his father, Gerrit van Eijken, who was organist and bell-ringer at the Grote Kerk in Amersfoort.
His elder brother Jan Albert van Eijken was also a composer.In 1859 the organist Karl Emanuel Klitzsch commented favourably in the Neue Zeitschrift fur Musik on his works.
But after initial successes he suffered from disappointment as a composer and became prey to alcoholism.
In his last years he earned a living as an organist in London, and died at the age of 46.