The intrinsically safe open channel mud level water level measuring instrument for mining is a real-time online detection instrument for open channel water level, mud level, and water flow impulse. The instrument uses optical principles to measure mud level and water level, uses lever principles to measure water flow impulse, and finally obtains instantaneous flow rate through upper computer software calculation and processing. Overcoming the difficulties in measuring and calculating underwater silt, this instrument has the characteristics of high measurement accuracy, easy operation, and all-weather automatic operation. It can be widely used for monitoring water level, mud level, and flow in mines, coal, petroleum, urban water supply, reservoirs, rivers, etc., especially suitable for installation in open channels with sediment deposition underground in coal mines.