<p>Blue light has been shown to impair spatial memory in mice. However, the underlying neural circuit mechanisms of this impairment remain elusive. Our study revealed that 600-lux blue light disrupted spatial memory retrieval in male mice through the secondary visual cortex (V2M) → the prelimbic cortex (PrL) neural pathway. Specifically, viral tracing and multichannel fiber optic recordings demonstrated that glutamatergic V2M neurons (V2M^Glu) projected to GABAergic neurons in the PrL (PrL^GABA), thereby inhibiting the excitability of glutamatergic PrL neurons (V2M^Glu→PrL^GABA→Glu). The selective ablation of V2M^Glu neurons projecting to the PrL eliminated the detrimental effects of blue light on spatial memory retrieval. Furthermore, optogenetic or chemogenetic activation of the V2M^Glu → PrL^GABA→Glu neural circuitry replicated the impairing effects of blue light on spatial memory in mice. Conversely, inhibition of the V2M^Glu → PrL^GABA→Glu neural circuitry reversed the spatial memory damage induced by blue light. Collectively, our findings elucidate the V2M^Glu → PrL^GABA→Glu neural circuitry as a potential mediator of blue-light-induced spatial memory impairment in male mice.</p><p></p>