Medicinal mushrooms have bioactive compounds with therapeutic properties. Lion’s Mane Mushroom is found throughout the northern hemisphere in Europe, Asia, and North America. The present investigation was conducted with the aim to determine the effect of organic and inorganic additiveon mycelium growth (spawn) of Lion’s mane mushroom (Hericium Spp.). In the present study organic additive viz. pulses flour (Pigeon pea) and cereal flour (Rice flour) @2% and inorganic additive (MgSo4) were mixed @1% as a supplement with wheat grains for spawn production of six different strains of Hericium. The results obtained during the present investigation, in the spawn production maximum mycelial growth (90.00 mm) was found in strain He-02 in the organic additive Pigeon pea flour and also in cereal flour (Rice flour) on 20th days, while maximum mycelial growth (90.00 mm) was also found in strain He-02 when Mgso4 was mix in wheat grains for spawn production of six strains of Hericium as inorganic supplements. Based on the results obtained, for spawn production of Lion’s mane mushroom (Hericium Spp.) strains He-02, by organic and inorganic supplementation, Pigeon pea flour and rice flour while in case of inorganic additive Mgso4 would be recommended most effective supplement in wheat grains for strain He-02.