Abstract. In this paper, we presented the Raabe's integral and Hermite's formula for q -gamma function Γ q (x) , 0 < q < 1 . We deduced new proofs of the formulasand q -Gauss's multiplication using the Hermite's formula of Γ q (x) and H. Jack's technique [11]. Also, we deduced new double inequality of Γ q (x) .Mathematics subject classification (2010): 33D05, 26D07, 65Q20.