Pleurotus ostreatus are large, oyster-shell shaped edible mushroom which can be easily identified by their grey white, oyster shell shaped cap which is attached to a thick, firm stalk. They are nutritionally rich contain good amount of vitamin C, niacin, riboflavin, thiamin and cobalamin. They have high oleic acid and linoleic acid content. They also contain lovastatin and pleuran. Hence, oyster mushroom exhibit anti-atherosclerotic, hypo-glycemic, anti-oxidant, anti-cancer and immuno-modulatory properties. P. ostreatus is one of the commonly sought wild mushrooms and paddy straw is mainly used as a substrate for its cultivation. Mycelial growth is a preliminary step that creates suitable internal conditions for fruiting. Thus, out-standing growth of mycelium is a vital factor in mushroom cultivation. In the present study, P. ostreatus cultivation was carried out using paddy straw as a substrate. Spawning was done in layers in polythene bags (24 ×16 inch). All the 10 spawned bags were arranged in a dark cropping room on raised platform for mycelium colonization of substrate. Suitable temperature (~28°C) and relative humidity (~80%) were maintained during incubation. Harvesting of mushrooms was carried out before the margin starts folding inwards. Observations such as days for spawn run, days for pinhead formation and first harvest, number of primordia, total weight and total yield of mushroom were measured in the study. It took 23.50 ± 1.27 days for spawn run and 27-31 days for pinhead. First harvest of fruiting bodies was done after the ~4th day of the pinhead formation. Total 224 primordia were noted up to the day of the first harvest from ten bags. The fruiting bodies were harvested into three flushes and total yield after 38 days of incubation was ~4.48 kg.