Impulse Buying merupakan perilaku membeli yang tidak disadari karena adanya pertimbangan unyuk membeli yang terjadi sebelum memasuki toko. Metode kuantitatif digunakan dalam penelitian ini dengan sampel dalam studi ini yaitu pelanggan Outlet Biru Yogyakarta sebanyak 100 responden. Teknik pengumpulan data menggunakan kuesioner skala likert. Teknik analisis yang digunakan yaitu dengan sobel test untuk mengetahui apakah ada hubungan melalui variabel mediasi yang memiliki kekuatan signifikan memediator dalam hubungan tersebut. Hasil penelitian membuktikan bahwa Fashion Involvement berpengaruh positif dan signifikan terhadap variabel Positive Emotion, variabel Shopping Lifestyle berpengaruh positif dan signifikan terhadap variabel Positive Emotion, variabel Positive Emotion tidak berpengaruh positif secara signifikan terhadap variabel Impulse Buying, variabel Fashion Involvement berpengaruh positif dan signifikan terhadap variabel Impulse Buying, variabel Shopping Lifestyle berpengaruh positif dan signifikan terhadap Impulse Buying.AbstractImpulse Buying is unconscious buying behavior because of the consideration or purchase intention that was formed before entering the store. The quantitative method used in this study with the sample in this study, namely the customer of Outlet Biru Yogyakarta as many as 100 respondents. The data collection technique used a Likert scale questionnaire. The analysis technique used is the sobel test to determine whether there is a relationship through the mediating variable which has a significant power to mediate in the relationship. The results of the study prove that Fashion Involvement has a positive and significant effect on the Positive Emotion variable, the Shopping Lifestyle variable has a positive and significant effect on the Positive Emotion variable, the Positive Emotion variable does not have a significant positive effect on the Impulse Buying variable, the Fashion Involvement variable has a positive and significant effect on the Impulse Buying variable, the Shopping Lifestyle variable has a positive and significant effect on the Impulse Buying variable.Keywords:Fashion Involvement; Impulse Buying; Positive Emotion; Shopping Lifestyle