In this paper we have investigated Bianchi Type-I cosmological model with varying cosmological constant A in f (R, T) theory of gravity. In order to obtain an exact solution of the field equations, we have used a special law of Hubble parameter proposed by Banerjee and Das (Gen Relat Gravit 37 (2005) 1695-1703), which leads to a time dependent deceleration parameter. We have discussed the physical and kinematical properties of the model in detail. The statefinder diagnostic parameters have also been considered. It has been shown that our universe model is consistent with the recent observations and approaches the ACDM model at late times.