Johannes Gijsbertus Bastiaans (1873-1953) was a Dutch composer and organist. He was born in Amsterdam and received his musical education at the Amsterdam Conservatory, where he studied composition with Bernard Zweers and organ with Hendrik Andriessen. Bastiaans is known for his organ music and choral works, as well as his symphonies and other orchestral pieces.
Bastiaans was also active as an organist and served as the organist of the Westerkerk in Amsterdam for many years. In addition to his composing and performing activities, Bastiaans was also a respected teacher, and taught at the Amsterdam Conservatory and other institutions.