The magnetic properties of Gd3Co11−xFexB4 for 2 ≤x≤4 have been investigated using 57Fe Mössbauer spectroscopy. These compounds have a hexagonal Ce3Co11B4 type of structure and are ordered ferrimagnetically for 2≤x≤4 at room temperature. The increase in the weighted average 57Fe hyperfine field for 2≤x≤4 is 19 kOe at room temperature, whose corresponding Fe moment is 0.13μB. In Gd3Co7Fe4B4 the Fe moments at the 2c, 6i 1 and 6i 2 sites obtained from the 57Fe hyperfine fields are 1.4, 1.1 and 0μB, respectively and the Fe atom at the 6i 2 site has no moment. The weighted average values of the isomer shift decrease with increasing Fe content.