References suggested that there are two components of body-image dysfunction: (a) perceptual body-size distortion and (b) cognitive-evaluative dysfunction. Also, reference indicated that an individual’s perception of body weight is an imperative component for understanding a dissatisfied body-image. Thus, the purpose of this study was to investigate female college students’ perceptions on their own body weight in relation to others. By analyzing college female students’ social perceptions on the deviation of their body weight in relation to a standardized normal female body weight, the study used the male students’ perceptions as a social standard of proper body weight image. Additionally, the reasons of the college students’ perceptions of deviation of body weight were also examined as well. The body image materials of PFRS (the female Photographic Figure Rating Scale) consist of ten photographic real female body images varying in body mass index (BMI) from emaciated to obese. Participants of the study were randomly selected from 6 universities and colleges, which included 1005 female students and 190 male students. The female participants were asked to choose the images in the PFRS representing their body size, ideal body size, and the most attractive body size respectively. To estimate the images of body weight based on the PFRS (assume that the image was as high as her), the participants were asked to report their actual body weight, and their perception on the desired ideal body weight. The male participants were asked to choose the most attractive body image from the PFRS. Based on the obtained research data, the attempt of this study was to reveal the female college students’ perceptions for the ideal body image so that the distance of deviation to ideal body image could be identified as well. In addition, the current study used three research models: (a) mirror model, (b) generalized model and (c) relevant model in order to reveal the reasons of the body weight perceptual deviation. The results of this study showed that the female students overestimated their own BMI (Body Mass Index); specifically, the female students tended to overestimate the BMI of the female students with normal weight or underweight, but underestimate the BMI of those overweight females. The score on the subjective social pressure of their body weight is higher than the real social pressure, which means that these students exaggerated the social pressure of body weight. Moreover, the female students’ perceptions on body image deviated to others were more possible to influence their self-perception deviation. Cognitive evaluation mentioned on the paper is not an important factor of weight perception deviation of the female college students, but the relation between these two factors should be further studied.