Abstract: A glass block window system for installation in a gypsum board wall is disclosed. The window system comprises a wall opening defined by a window frame comprising a sill stud, a header stud and first and second jamb studs. A hollow metal frame defines a window opening. The frame includes frame members comprising a sill member, a header member, and first and second jamb members joining the sill member and the header member. A block channel comprising a sill channel, a header channel and first and second jamb channels is secured to the frame members. A plurality of contiguous glass blocks forming a window unit is secured within the block channel.