A polyarylene sulfide resin powder/grain composition in which 100 weight parts of polyarylene sulfide resin powder/grain material whose average particle diameter exceeds 1 μm and is less than or equal to 100 μm and whose uniformity degree is less than or equal to 4 has been blended with 0.1 to 5 weight parts of an inorganic fine particle having an average particle diameter greater than or equal to 20 nm and less than or equal to 500 nm.