Green Moldresponsible for the reduction in yield of Ganoderma mushroom, a higher temperature mushroom, were isolated and identified. Based on symptomatology and morphological characteristics of the green moldthe pathogen was identified as Trichoderma atroviride showing an incidence of 68.9 -70 percent, respectively. The studies conducted under in vitro conditions indicated the efficacy of Bavistin (0.1%, 0.05%, and 0.025%), Antracol (0.1%, 0.05%, and 0.025%), Dithane M-45 (0.1%, 0.05%, and 0.025%) to control green mold (Trichoderma Atroviride). However, Trichoderma Atroviride was controlled under in vivo conditions by spraying the after-bag opening (in pinheads’ formation) area of the compost bag (substrate media). Among the sprays of different fungicides in case of incidence of Trichoderma Atroviride, maximum yield was recorded by Bavistin (0.1%) – 157.6 gm/bag, Bavistin (0.05%} – 150.7 gm/bag, Antracol (0.1%) – 148.1 gm/bag and Bavistin (0.025%) – 138.9 gm/bag, respectively. These fungicides (Bavistin, Antracol, and Dithain M-45) did not affect the spawn run and were found beneficial to increase Ganoderma mushroom yield from 38-65%over control.