A Ni-based heat resistant alloy for a gas turbine combustor, comprising a composition containing, in mass %, Cr: 14.0 to 21.5%, Co: 6.5 to 14.5%, Mo: 6.5 to 10.0%, W: 1.5 to 3.5%, Al: 1.2 to 2.4%, Ti: 1.1 to 2.1%; Fe: 7.0% or less, B: 0.001 to 0.020%, C: 0.03 to 0.15%, and a balance consisting of Ni and unavoidable impurities, wherein a content of S and P contained in the unavoidable impurities is controlled to be, in mass %, S: 0.015% or less, and P: 0.015% or less, wherein the alloy has a texture in which M6C type carbide and MC type carbide are uniformly dispersed in γ phase matrix.