BackgroundSexual self-esteem and communication on sexual issues with a partner contribute greatly to an individual's quality of sex life; however, their effects on the relationship between body image and sexual function are underexplored. AimTo test a serial mediating pathway of sexual self-esteem and sexual communication underlying the relationship between body image and sexual function. MethodsA total of 510 women aged 18–53 years (mean = 28, SD = 5.5) who were involved in an intimate relationship completed an online survey. OutcomesWomen's (i) body appreciation, (ii) body image self-consciousness during sexual intimacy, (iii) sexual self-esteem, (iv) dyadic sexual communication, (v) negative disclosure apprehension, and (vi) sexual function were assessed. ResultsFindings revealed that sexual self-esteem and dyadic sexual communication played a serial mediating role in the relationship between body image (body appreciation and body image self-consciousness during sexual intimacy) and sexual function, and the relationship between body image and arousal, lubrication, orgasm, satisfaction, and pain. Sexual self-esteem and negative disclosure apprehension also played a serial mediating role in the relationship between body image and sexual pain. In addition, dyadic sexual communication played a unique mediating role in the relationship between body image and sexual function, which is isolated from the effect of sexual self-esteem. Clinical ImplicationsWomen's sexual self-esteem and sexual communication with their partner can make beneficial contributions to the relationship between body image and sexual function. Therefore, promoting women's positive body image, sexual self-esteem, and sexual communication skills deserves attention from women themselves and clinicians. Strengths & LimitationsThis study used a robust method of data analysis to test the mediating effect of sexual self-esteem and sexual communication to clarify the mechanism underlying the relationship between body image and sexual function among Chinese women; however, causal conclusions cannot be drawn. Furthermore, various demographics including participants' age, education level, sexual orientation—factors such as relationship status and length, relationship functioning, and partner-related variables—and other aspects of sexual self-concept and sexual communication should be examined in future research. ConclusionThe current study indicates that women's thoughts and feelings regarding sexuality and communicating sexual issues with their partner are associated closely with their body image and sexual function.T Wu, Y Zheng. Effect of Sexual Esteem and Sexual Communication on the Relationship Between Body Image and Sexual Function in Chinese Heterosexual Women. J Sex Med 2021;XX:XXX–XXX.