The invention relates to a training system and an operation method thereof, in particular to a liquid level measurement and control training system and an operation method thereof. The liquid level measurement and control training system comprises a liquid level measurement and control training device and a control panel, wherein the liquid level measurement and control training device comprises a base plate, a main support, a water storage tank, a controlled water tank, a water pump motor, a drainage solenoid valve, a manual water inlet valve, a manual drainage valve, a water inlet of the water storage tank, a water outlet of the water storage tank, a flooding pipe, a water inlet pipe, a water outlet pipe, an air vent, a water inlet of the controlled water tank, a water outlet of the controlled water tank, a liquid level follower plate, a floating shaft, a pressure sensor, an upper liquid level detection sensor, a middle liquid level detection sensor, a lower liquid level detection sensor, an ultrasonic locating probe and a line access control cabinet. The operation method comprises the following steps of: determining training content according to teaching requirements; selecting a corresponding control module to complete wire connection among the training devices; selecting a liquid level detection device to complete line connection; switching on an air switch for power on so as to complete system debugging; and starting a training process.