This study was done to research the relationship between State-Trait Anxiety and Sexual activity of pregnant women. The subjects for this study were 200 pregnant women from 2 hospitals located in a urban area. The data was collected through questionnaires which was developed by Spielberger, from to, 1982. The content of the questionnaire consist of following 2 categories of Anxiety and Sexual activity; (1) State Anxiety, (2) Trait Anxiety and (3) Sexual activity included sexual drive, number of sexual intercourse, and length of sexual intercourse. Analysis of data was done by use percentage, T-test, x$^2$-test, ANOVA and pearson correlation coefficiency. The findings of this study are as follows: 1. The mean score of state Anxiety and Trait Anxiety of respondents were 43.06, 44.19, therefore Trait Anxiety was higher than state Anxiety. 2. A significant state Anxiety and Trait Anxiety were not found among general characteristics with age, education level and religion 3. In the analysis of correlation among state Anxiety, Trait anxiety and Sexual activity, the Trait Anxiety was positively correlated with the State Anxiety. (r=.3877, p=.000) It was support the fact that the higher level of Trait anxiety, the greater was the State anxiety. 4. And the state anxiety was negatively correlated with number of sexual intercourse. (r=-1518, p=.016) Therefore, the higher the state anxiety, the lower sexual activity. Or the lower sexual activity, the higher the State Anxiety. 5. Also, in the analysis of factors affecting sexual activity, only the variable of age showed a significant correlation to number of sexual intercounse. That is the younger, the higher number of sexual intercounse. (r=. -. 1380, p=.026).