Presented here are two novel porous supramolecular boron imidazolate frameworks (BIF-106 and BIF-107), which are stabilized through relatively weak interactions between two-dimensional boron imidazolate layers. Moreover, BIF-107 exhibits efficient CO2 photoreduction to CO with a remarkable rate of 1186.0 mu mol.g(-1) .h(-1) under visible-light irradiation.