PURPOSE: To provide both flame retardant properties and humidity-solder resistant properties while high heat resistant properties and peeling strength are maintained by employing a prepreg composed of an aromatic polyamide fiber substrate impregnated with epoxy resin composition.

CONSTITUTION: Epoxy resin mainly composed of specific epoxy resin and hardner mainly composed of specific phenolic hardner are mixed so as to have a phenolic hydroxide radical equivalent ratio of 0.6-1.3 to an epoxy equivalent. After that, additive such as hardening accelerator is added to the epoxy resin composition. A prepreg is composed of an aromatic polyamide fiber substrate impregnated with the epoxy resin composition. Required number of prepreg sheets are laminated and a copper foil is applied to the surface of the laminated prepreg sheets and the copper foil and the prepreg sheets are molded a solid body by pressure heating. The copper-clad laminated board thus obtained has a surface direction linear thermal expansion coefficient as small as that of a silicon bare chip. Therefore, even if the corper-clad laminated board is used as a board for chip-on-board, crackings are not created in a die- bonding part. With this constitution, both flame resistance and humidity-solder resistant properties are provided while high temperature resistant properties, hardness and peeling resistance are maintained.