To provide a method for manufacturing a composite member, in which a component made of ferrous material is surrounded with aluminum alloy by a casting process, and which can secure the adhesiveness and bonding strength of an interface.

A cylinder block 4, which is a composite member composed of a cylinder liner 1 made of ferrous material and a cylinder block body 3 made of aluminum alloy, is manufactured in such a manner that the outside peripheral surface 2 of the cylinder liner 1 made of ferrous material is treated by shot blasting using granular blasting material 5 which is a metal containing Zn as a main component, and then is surrounded with an aluminum alloy by the casting process. Minute uneveness is formed on the outside peripheral surface 2 of the cylinder liner 1 by shot blasting, and further the blasting material sticks to the outside peripheral surface 2 with a comparatively uniform thickness. The stuck blasting material melts into molten aluminum alloy, and the molten aluminum alloy closely intrudes into the outside peripheral surface 2 of the cylinder liner 1 without gaps. As a result, the cylinder block 4 having the tightly adhering interface 7 can be manufactured.