Background Episodic memory loss is a prominent clinical manifestation of Alzheimer's disease(AD), which is closely related to tau pathology and hippocampal impairment. Given the heterogeneity of brain neurons, the precise role of different brain neurons in terms of their sensitivity to tau accumulation and contribution to AD-like social memory loss remains unclear and requires further investigation. Methods We investigated the effects of AD-like tau pathology by Tandem mass tag proteomic and phosphoproteomic experiments, social behavioral test, hippocampal electrophysiology, immunofluorescent staining and in vivo optical fiber recording of GCaMP6f and iGABASnFR. Additionally, we utilized optogenetics and administered ursolic acid via oral gavage to examine their effects on social memory in mice. Results By proteomic and phosphoproteomic analyses, we identified the characteristics of ventral hippocampal CA1 (vCA1) under both physiological conditions and AD-like tau pathology. As tau progressively accumulated, not dorsal CA1(dCA1), but vCA1, especially its excitatory and PV neurons, were fully filled with mislocated and phosphorylated tau. Overexpression of human Tau (hTau) in excitatory and PV neurons respectively mimicked AD-like tau accumulation, significantly inhibited the neuronal excitability and suppressed distinct discrimination-associated firings of these neurons within vCA1. Photoactivating excitatory and PV neurons in vCA1 at specific rhythm and time-window efficiently ameliorated tau-impaired social memory. Significantly, one-month administration of ursolic acid (UA) efficiently decreased tau accumulation via autophagy in a TFEB (transcription factor EB)-dependent manner and recovered vCA1 microcircuit to ameliorate tau-impaired social memory.