Disclosed is a processing apparatus including a processing portion, an actuator, a casing, a preload mechanism, a force sensor, and a detection unit. The processing portion includes a cutting edge. The actuator is configured to cause the processing portion to vibrate microscopically. The casing is configured to accommodate the actuator. The preload mechanism is disposed inside the casing and configured to impart a preload to the actuator. The force sensor is disposed between the cutting edge and the preload mechanism. The detection unit detects a cutting force of the processing portion based on an output of the force sensor. The invention can detect cutting force as well as form miniature or complicated three-dimensional pattern with high precision.