The compact load sensor we developed uses an AT-cut quartz crystal resonator whose resonance frequency changes under external load, featuring high sensitivity, high-speed response, and a wide measurement range – plus superior temperature and frequency stability. The vulnerability of previous quartz crystal resonators to stress concentration in bending prevented them from being more widely applied to load measurement. The sensor we developed maintains the quartz crystal resonator safely. Our objective here is to improve load measurement resolution and to miniaturize the sensor, which we did designing novel retention of the quartz crystal resonator fixed vertical to applied load. The new load sensor’s resolution is 3.21 mN –seven times better than conventional load sensors.