Cooling fin fixing structure

The invention provides a cooling fin fixing structure, which is suitable for accommodating of cables of electronic products. The fixing structure comprises a cooling fin with a first locking hole, a mainboard with a second locking hole, and a locking piece which comprises a fixed column, an elastic arm, a gasket and a locking arm; the fixed column comprises a column body and a clamping hook; a containing groove is formed between the column body and the clamping hook; the gasket is provided with a through hole; when an external force is applied to the locking piece, the locking arm penetrates through the first locking hole of the cooling fin and the second locking hole of the mainboard, the gasket is abutted with the cooling fin, and the elastic arm is pressed to be bent for enabling the clamping hook to penetrate through the through hole of the gasket, the first locking hole of the cooling fin and the second locking hole of the mainboard; and when the external force is released, the locking arm enters the con