A vehicular exterior door handle assembly includes a base portion configured to mount at an exterior door handle region of a vehicular door of a vehicle, a handle portion, and a sensing module that includes a light emitter and a light sensor. With the base portion of the handle assembly mounted at the exterior door handle region of the vehicular door, the light emitter is episodically energized to emit light. When the light emitter is not energized to emit light, the light sensor senses ambient light at the handle portion, and when the light emitter is energized to emit light, the light sensor senses emitted light emitted by the light emitter. The sensing module determines presence of a person's hand at the handle portion based at least in part on a difference between the sensed ambient light and the sensed emitted light being below a threshold light level.