Alpha amylase (α amylase) is one of the main enzymes used in various sectors such as food, textile, paper and detergent industries. Microbial production of α amylase using solid state fermentation (SSF) system appears as a promising technology now. Several parameters such as incubation period, incubation temperature, initial pH of the media, substrate content etc. affect the production of α amylase in SSF system. The present study focuses on the production of α amylase from the fungus Aspergillus oryzae and also optimization of various fermentation parameters using banana peel as a substrate. Incubation period of 96 hours, incubation temperature 35°C, initial pH of the medium at 5.0 and 50 g of substrate were found to be optimum for the production of á amylase by Aspergillus oryzae through SSF process.