This study aims to improve the comfort and fit of womens swimsuits. Based on the results of the survey, trial suits were designed. In terms of the breast cap, there are five variations based on the feature, size, and thickness and two variations according to the connection mode of the cap. Total 17 trial swimsuits were made, ease of movement and wearing comfort were evaluated. The results of this study were as follows: 1. In terms of movement according to the type of breast cap, the round type shelved much less movement than the triangular type at the lower part of the cap. According to size, the cap that was manufactured on the basis of brassiere cup size showed much less movement than the ordinary cap size in the same round type of cap. In terms of the connection mode between breast caps and swimsuits, there was less cap movement when they were connected by power nets compared to the ordinary models which were connected by conventional rope. 2. Analysis of the differences in wearing comfort. The round type proved to be more convenient than the triangular type at the lower circumference of the caps, the power net collection was rated more positively by the respondents.