To obtain a composite material which has high thermal conductivity equal to or higher than that in the case where diamond is used, and has excellent workability as well.

The composite material is obtained by dispersing blended particles 13 consisting of SiC as hard particles 11 and carbon nanotubes 12 formed around the hard particles 11 into a metal matrix 14. The boundary layers S between the hard particles 11 and the metal matrix 14 are clad layers between the carbon nanotubes 12 and metal. The volume ratio of the carbon nanotubes 12 to the total volume of the blended particles 13 is 50 to 90%.