A composition for producing a metallic sintered body consisting essentially of a mixture of a powered metal having an average particle size of not more than 50 microns with a lactone resin having a relative viscosity value in the range of from 1.15 to 3.20 is disclosed.The composition has excellent properties such as mechanical strength of a green body thereof, and only a short time being necessary for removal or elimination of binder in comparison with conventional sintering compositions.Furthermore, the binder in the present composition is substantially composed of a single component; accordingly, manufacturing process control can be simplified by use of the lactone resin.Furthermore, a method for producing a metallic sintered body using such composition is also disclosed.