The utility model discloses a washing machine's water level sensing apparatus and washing machine who has it, washing machine's water level sensing apparatus includes: level sensor and air chamber skirt, the air chamber skirt includes first pipeline section and second pipeline section, and first pipeline section is suitable for the back outer bucket that is connected to washing machine in order tohold gas and water, holds gaseously in the second pipeline section and is connected to level sensor, and the internal diameter of second pipeline section is lighter than the internal diameter of first pipeline section, first pipeline section and second pipeline section integrated into one piece. According to the utility model discloses washing machine's water level sensing apparatus is through setting up the air chamber skirt first pipeline section and the second pipeline section for having different internal diameters to making the internal diameter of second pipeline section be lighter thanthe internal diameter of first pipeline section, making outside washing machine back in the bucket under the same circumstances of water -level fluctuation, the pressure variation in the second pipeline section is sensitiveer, and then improves detecting reliability, and set up first pipeline section and second pipeline section into integrated into one piece, thus simplification structure, improvement reliability.