A chip heat sink for a chip and a nucleic acid extraction device, where the chip has a channel for conveying a fluid, and on/off of the channel is controlled by an solenoid valve, the chip heat sink includes: a substrate, where the substrate has a first surface for placing the chip, and the first surface is provided with a first accommodating groove for accommodating an electromagnet; and a heat dissipation structure on the substrate and for dissipating heat from the electromagnet.