Tricholoma giganteum Massee (Syn-Macrocybe gigantea), another edible summer mushroom is widely distributed in tropics of Asia and Africa. In India it is mostly seen in Hooghly, West Bengal. It is pure white in colour and resembling the morphology of Calocybe indica. An experiment was carried out during the summer season, 2018-2019 to study the effect of various casing mixtures on yield performance of T. giganteum (TGSLM). The casing soil affects not only initiation of fruiting bodies, number of pinhead formation but also duration of mushroom, yield and biological efficiency. To overcome this issue casing soil were tested with various parameters for the cultivation of milky mushroom. Among different casing mixtures, red soil + sand (1:2) recorded minimum days for pinhead formation (13.32 days), number of pin head initiation (102.13), number of fruiting bodies (31.29), yield (1698.82 g/bed) and biological efficiency of 169.88 per cent and showed the better performance for the production of T. giganteum (TGSLM).