The present invention herein relates to fastening structure for a heat sink to provide a fastening structure easy and convenient both for assembling and disassembling operation, characterized by fastening structure being a material of elasticity comprising a controlling member and a motioning member, wherein controlling member is composed of a reinforcing loop, a operational portion of controlling member and a first radian claw, a motioning member buckling up controlling member is composed of a operational portion of motioning member and a second radian claw, heat sink for assembling and disassembling operate in coordination with a first radian claw, a second radian claw and a reinforcing loop