This research was carried out to test the effect of three basic preservation methods cooling, canning and freezing on the nutritional value of mushroom Agaricus bisporus. Mushroom were picked from a private sector then stored for 20 weeks. Chemical analyses of mushroom were conducted at three phases: at time zero which means immediately after preservation, after ten weeks and after 20 weeks. Sodium benzoate 5% and potassium serrate and 5% were tested as preservatives.