Objective: To study the features in the pulse waves of women during pregnancy. Methods: To collect the pulse waves of pregnant women in different stage and compare them with normal women's. We choose continuous cycles waves with different period length and then do the LSQ regression by 12 harmonics fitting to build mathematical model and extract 193 parameters after pretreatment, then do classification and identification to find the features. Result: There are significant difference between pregnant women's pulse waves and the normal women's and the accurate is 86% to identify, the features distribute at different places in radial artery called “cun” “guan” “chi” in pulse-diagnosis of TCM. The identification accurate of first trimester is 86%, and second trimester's is 89%, 94% is the third's. Features of each stage focus on the special place of radial artery. Conclusion: Physiological changes of pregnant women can embody in pulse waves we collected from the radial artery and the characters change regularly during the different stage of pregnancy. This research can offer some scientific basis for diagnosing pregnancy by taking pulse in TCM and also for the method of pulse-taking to feel different places in radial artery.