Objective To investigate the effects of arginine vasopressin 1b receptor (Avpr1b) gene knockout on the plasma corticosterone level, anxiety, and social behaviors in female rats. Methods Female AvpR1b knockout (AvpR1b^KO ) and wildtype (WT) SD rats were used. First, the expression levels of Avpr1b in the paraventricular nucleus (PVN) and supraoptic nucleus (SON) of the brains of WT and AvpR1b^KO rats were examined by performing in situ hybridization. The basal plasma corticosterone levels of WT and AvpR1b^KO rats were then analyzed by conducting high- performance liquid chromatography tandem high-resolution mass spectrometry. Additionally, the anxiety levels of rats were evaluated by using an open field test and elevated plus maze test. Finally, the social ability and social novelty of WT and AvpR1b^KO rats were measured by performing a three-chamber experiment. Results There was no expression of AvpR1b in paraventricular nucleus or supraoptic nucleus of AvpR1b^KO rats. The basal plasma corticosterone level of AvpR1b^KO rats was not significantly different from that of WT rats (P>0.05). The duration and bouts of AvpR1b^KO rats entering the central area in the open field experiment were not different from those of WT rats ( P> 0.05). Similarly, the duration and bouts of AvpR1b^KO rats entering the open arm area in the elevated plus maze were not different from those of WT rats (P>0.05). In the social interaction experiment, the socialbility index of AvpR1b^KO rats was not different from that of WT rats (P>0.05). In the social novelty experiment, the social novelty index of AvpR1b^KO rats was not different from that of WT rats ( P> 0.05). Conclusions A knockout of AvpR1b in female SD rats does not affect their basal plasma corticosterone level, anxiety level, sociability, or interest in social novelty.