To provide raw material powder of a sintered compact of an aluminum nitride system having high thermal conductivity, a low coefficient of friction and excellent wear resistance and a method of manufacturing for the same.

Aluminum nitride powder, boron nitride powder and metallic titanium powder are mixed at an acceleration of 5 to 200 G at room temperature to 250°C in a nitrogen atmosphere, by which the aluminum nitride-base composite powder consisting of the aluminum nitride, titanium nitride, boron nitride and titanium boride all having an average grain size of ≤30 nm and at least the phase having amorphous covering their particle surfaces and having the average grain size of ≤0.3 μm is obtained. The pressure of the nitrogen atmosphere is preferably 0.05 to 1.0 MPa, the amount of the metal titanium powder to be added 5 to 50 wt.%, the amount of the boron nitride powder to be added 2 to 40 wt.% and the mixing time 0.5 to 50 hours.