India is one of the largest producers of commercial vegetables and spices, including chilli (Capsicum annuum L.). To reduce postharvest losses and enhance value addition, green chilli preparation and preservation are important. The aim of the present study is to investigate the effect of different chemical pretreatments on green chilli powder quality as well as the effect of storage on its quality. The experiment was laid out in the Factorial Completely Randomized Design (FCRD) with eight different pre-treatments and three storage intervals. The significantly lowest L*, a* and b* colour values and the significantly maximum solubility, total ash, crude fiber, acidity, ascorbic acid, total phenol and capsaicin were observed during 180-day storage period in the pre-treatment of green chilli with 1% ascorbic acid by dipping for 10 min. During the 180-day storage period, the Total Plate Count was increased but remained within permissible limit. The maximum protein content was observed in pre-treatment with 0.3 % sodium metabisulphite, while the lowest Total Plate Count was recorded in pre-treatment with 0.5 % chitosan. Based on the study of various parameters, dipping green chilli in 1 % ascorbic acid for 10 min followed by tray drying produced superior quality. The green chilli powder was stored for a duration of 180 days under ambient conditions.