Objective:To detect the effects of 17β-estradiol on the survival of cortical hippocampal neurons and determine whether it is associated with nNOS/PSD95 complexes. Methods:ICR mice was adopted to culture cortical hippocampal neurons. Eight days later, lactate dehydrogenase(LDH) release rate were examined in cultured cortical hippocampal neurons exposed to DMSO or 10 μmol/L 17β-estradiol for 30 min. The neurons were photographed through a light microscope. Meanwhile, nNOS/PSD95 complexes of neurons treated with DMSO,10 nmol/L 17β-estradiol and 10 μmol/L 17β-estradiol were measured by co-immunoprecipitation. Results:At 30 minutes after administration, 10 μmol/L 17β-estradiol treatment increased LDH release rate and nNOS/PSD95 conjugating in cortical hippocampal neurons, and 10 nmol/L 17β-estradiol treatment had no influence on nNOS/PSD95 conjugating. Conclusion:17β-estradiol of 10 μmol/L could injure cortical hippocampal neurons by promoting the conjugating of nNOS and PSD95.