Ge‐based hybrid perovskite materials have demonstrated great potential for second harmonic generation (SHG) due to the geometry and lone‐pair induced non‐centrosymmetric structures. Here, we report a new family of hybrid 3D Ge‐based bromide perovskites AGeBr3, A=CH3NH3 (MA), CH(NH2)2 (FA), Cs and FAGe0.5Sn0.5Br3, crystallizing in polar space groups. These compounds exhibit tunable SHG responses, where MAGeBr3 shows the strongest SHG intensity (5×potassium dihydrogen phosphate, KDP). Structural and theoretical analysis indicate the high SHG efficiency is attributed to the displacement of Ge2+ along 111 direction and the relatively strong interactions between lone pair electrons of Ge2+ and polar MA cations along the c‐axis. This work provides new structural insights for designing and fine‐tuning the SHG properties in hybrid metal halide materials. A new family of non‐centrosymmetric hybrid Ge‐based bromide perovskites are reported, showing second harmonic generation (SHG) responses. The largest SHG signal from CH3NH3GeBr3 is likely due to the perferable alignment of the polar cation with the lone pair electrons of Ge2+ along the 111 direction.