Power Reception Device, Wearable Device, and Non-Contact Power Feeding System

Provide are a power reception device, a wearable device, and a non-contact power feeding system that can improve the transmission efficiency while suppressing upsizing of the circuit thereof. A power reception device () includes a variable capacitance circuit () and a power reception coil () constituting a resonance circuit together with the variable capacitance circuit (), in which the variable capacitance circuit () includes a first capacitor (C) and a second capacitor (C) connected in parallel to each other, a first switch (Tr) connected in series to one end side of the first capacitor (C), and a switch control circuit () that controls turning on and off of the first switch (Tr) and includes a first comparator (OP) that supplies a first control voltage to the first switch (Tr) according to a comparison result between a reference voltage and an AC voltage applied to the second capacitor (C).