Organic halide perovskite solar cells (PSCs) with high power conversion efficiency (PCE) and low manufacturing cost have been attracting considerable attention. However, defects in perovskite as recombination centers and ion migration paths seriously deteriorate the optoelectronic performance of PSCs. Herein, a facile strategy is devised by introducing sodium glycinate (SG) mulit-functional additive into perovskite to passivate defects. In this way, the typical defects of mismatched leads in perovskite can be passivated by forming ionic bond with carboxylate radical or coordination bond with amino groups of SG. Also, the SG molecules with cross-linking function could improve the grain sizes of perovskite to reduce defects and increase light absorption. Besides, sodium ions of SG can impede the ion migration in perovskite and strengthen the interfacial charge transfer ability. As a result, the PSCs assembled under air condition with SG additive achieved a champion conversion efficiency of 19.32 % due to the comprehensive action of SG, and an improved stability under work and storage conditions. This provides an economical and effective strategy for the industrialization of PSCs.