Background: Individuals may find it challenging and discomforting to communicate about sex because they may lack the skills and efficacy necessary to communicate their sexual desires. When individuals do have opportunities to have such discussions about sex in open and comfortable settings, they may seek informational support (i.e., advice) from a close friend because of knowledge sharing and past experiences navigating sex-related concerns. Aims: This research study used a communication theory-based quantitative analysis to examine how advice givers' prosocial behaviors influence their advice outcome messages during conversations about sex. Methods: A total of 264 participants completed a survey developed based on the Integrated Model of Advice-Giving (IMA). Data were analyzed using structural equation modeling. Results: Advice givers reported that their emotional supportive messages elicited better quality advice. Additionally, advice givers indicated that being attentive and understanding to others' feelings elicited better disclosures about their own sexual experiences. Structural equation modeling results suggested a good model fit for the theoretical model (comparative fit index [CFI] = 0.939, tucker-lewis fit index [TLI] = 0.931, root mean square error of approximation [RMSEA] = 0.056, 90% confidence interval: [0.049, 0.063], and standardized root mean square residual [SRMR] = 0.082). Conclusions: This study highlights the theoretical and pragmatic implications of communication theory in sexual health education interventions.