This study investigates how using a specific SNS platform has impact on users’ self-construals. Also, this research examines the effect of the association between SNS platforms and users’ self-construals in improving the efficacy of advertising in SNSs. Based on self-construal theory and information processing model (affective vs. cognitive processing), it is assumed that users’ self-construals can be primed by their SNS use and the primed self-construals can have impact on their information processing in SNS contexts. Two laboratory experiments were conducted to test these assumptions. A total of 191 (Study 1 – 74 & Study 2 – 117) undergraduate students participated in this research. The findings from study 1 empirically supported that SNS platforms could prime users’ self-construals differently. The results from Study 2 not only provided compatible evidence that SNS platforms can change users’ self-construal but also demonstrated the interplay between the primed self-construal by SNS platforms and ad types (emotional appeal vs. cognitive appeal ad) in shaping individuals’ response toward the ad. Also, the mediating role of users’ self-construal on the interplay between SNS platforms and ad types.was confirmed. Since the current research tested two image-based SNS platforms with undergraduate students, future research may need to test different population with more various platforms to re-examine the findings from this study. The current research contributes to the field by expanding the self-construal concept in SNS research, as well as provides practical implications to improve the efficacy of SNS advertising campaigns.