The research aims to discover the effect of KMnO4 concentrations towards the shelf life of curly red chili peppers. And obtain the best concentration of KMnO4 to extend the shelf life of curly red chili peppers. The research was conducted in the Post-harvest Laboratory of Agricultural Faculty, University of Muhammadiyah Yogyakarta, October 2016. The research was compiled in a Completely Randomized Design (RAL), with a single factor that is KMnO4 treatment appswhich consist of 4 treatments with 3 replications (3 times trial). The treatments were consist of: KMnO4 applications with 0% concentrations, KMnO4 applicatios with 0.05% concentrations, KMnO4 applications with 0.10% concentrations, and KMnO4 applications with 0.15% concentrations. The results showed that there was positive effect in concentration of KMnO4 towards the shelf life of curly red chili peppers, 0,10 % of KMnO4 concentration was the best concentration to extend the shelf life of curly red chilies (Capsicum annuum L).