This study explored whether there were correlations among internal and external control personality traits, fashion anxiety, online word of mouth, the Bandwagon effect, and consumer involvement. The online questionnaire was adopted in this study, with online consumers who used new shopping websites as sample sources. After deleting invalid questionnaires, there were 265 valid samples. The analysis results show that: (1) Consumers with the fashion anxiety characteristic care more about others and are subject to external influence. Therefore, internal and external control personality traits have a significant positive impact on fashion anxiety; (2) Consumers with external control personality traits are more likely to believe others or the external environment, leading to greater likelihood for the Bandwagon effect to result. Therefore, the internal and external control personality traits produce a positive impact on the Bandwagon effect; (3) Internal and external control personality traits produce a significant positive impact on online word of mouth; (4) Consumer involvement varies with different personality traits. Therefore, internal and external control personality traits produce a significant positive impact on consumer involvement; (5) Consumers with fashion anxiety characteristic are likely to follow others. Therefore, fashion anxiety produces a significant positive impact on the Bandwagon effect; (6) The results on the interaction between consumers’ Bandwagon effect and online word of mouth show that the Bandwagon effect and online word of mouth have a reciprocal effect; (7) Consumer involvement produces a significant positive impact on the Bandwagon effect; (8) compared to consumers with higher involvement, consumers with lower involvement trust online word of mouth more. Therefore, consumer involvement produces a significant positive impact online word of mouth.