Together, our findings indicate that the mossy cell pathological tau accumulation could induce the AD‐like spatial memory deficit by inhibiting the local neural network activity, which not only reveals new pathogenesis underlying the mossy cell‐related spatial memory loss but also provides a mouse model of Mossy cell‐specific hTau accumulation for drug development in AD and the related tauopathies. Here, MAPT is linked to Alzheimer disease.