〔Abstract〕 Objective To compare the effect of rigid/flexible artificial insemination catheter on pregnancy outcome of artificial insemination by donor. Methods The clinical data of 2 747 artificial insemination by donor(AID) cycles were analyzed retrospectively. According to the rigid/flexible artificial insemination catheter used in the operation, they were divided into rigid catheter group and flexible catheter group. According to the follicular development scheme, they were furtherly divided into rigid catheter-natural cycle group, rigid catheter-promoted ovulation cycle group, flexible catheter-natural cycle group and flexible catheter-promoted ovulation cycle group. And according to the times of intrauterine insemination(IUI) in each AID cycle, they were furtherly divided into rigid catheter-single insemination group, rigid catheter-double insemination group, flexible catheter-single insemination group and flexible catheter-double insemination group. Then the biochemical pregnancy rate, clinical pregnancy rate, live birth rate, multiple pregnancy rate and abortion rate among the groups were compared and analyzed. Results The biochemical pregnancy rate, clinical pregnancy rate and live birth rate of the flexible catheter-single insemination group were higher than those of the rigid catheter-single insemination group, and the difference had statistical significance(P<0.05). The difference between the abortion rates of the two groups had no statistical significance. In addition, the biochemical pregnancy rate, clinical pregnancy rate, live birth rate, multiple pregnancy rate and abortion rate of other rigid catheter groups and flexible catheter groups had no statistical significance(allP>0.05). Conclusion There is no difference in pregnancy outcome between using flexible catheters and rigid catheters in AID treatment. However, when there is only single IUI in an AID cycle, the pregnancy outcome of using flexible catheters is better than that of using rigid catheters.