An adjustable heat exchanger includes a fan assembly, a heatsink assembly, a semiconductor chilling plate and a conduction cooling unit connected in sequence, the conduction cooling unit includes a main conduction cooling plate and a conduction cooling which includes at least one conduction cooling sub-fin. The main conduction cooling plate is connected to the semiconductor chilling plate, the conduction cooling fin is movably connected to an outer peripheral wall of the main conduction cooling plate, the conduction cooling fin extends outward along the center of the main conduction cooling plate, and the conduction cooling fin and the main conduction cooling plate jointly form a contact surface for adapting to a heat-dispersing surface. The present heat exchanger can adapt to hot surfaces with different curved surface radians and form a surrounded fixed structure with the hot surface to make the conduction cooling unit well-contact surfaces with different radians.