The purpose of this study is to apply the expectancy disconfirmation model to consumer post-purchase behavior toward fast fashion brands. This study incorporated repurchase intention as a result of consumer satisfaction. It was hypothesized that consumer satisfaction, which is influenced by expectation, perceived performance, and disconfirmation, influences repurchase intention. It was also hypothesized that expectation influences performance. This study examined the brands and prices of the most recent purchases of fast fashion and also examined whether the purchases were planned or unplanned. The hypothesized path was tested and the relative influences of instrumental and symbolic performance on satisfaction were identified. Data were collected from questionnaires answered by 344 university students who were selected by convenience sampling. The results were as follows: 1) Purchased brands were, in the order of frequency of purchase, Uniqlo, Zara, H&M, and Forever21, followed by domestic brands, 8seconds, Spao, and Mixxo. The frequency of unplanned purchase was more than twice higher than planned purchase. 2) Based on expectation and performance, dissatisfactory group was larger than satisfactory group, which were 35.8% and 24.7% respectively. 3) It was revealed from the expectancy disconfirmation model analysis that expectation and performance had positive influence, but cognitive dissonance had negative influence on satisfaction. Satisfaction had significant influence on repurchase intention. The path analysis showed that all hypothesized path coefficients were significant. The results suggest some effective marketing strategies for marketers in the fast fashion industry.