A system for attaching a gutter profile and a rod of a greenhouse to each other comprises a gutter profile which is made of extruded aluminium and is provided with a through—hole in a wall thereof, a rod which is made of extruded aluminium and which is mountable to the gutter profile such that in a mounted condition the rod is supported by the gutter profile and extends transversely with respect to the gutter profile, and a rigid locking element for interlocking the rod and the gutter profile in longitudinal direction of the gutter profile. The locking element comprises a protruding portion which fits in the through—hole and a fixation portion which is attachable to an end portion of the rod. In the mounted condition the protruding portion extends through the through— hole.
