The invention relates to the field of detectors, in particular to a pesticide residue detector. The pesticide residue detector includes a base, a storage battery is fixedly connected in the base, a sliding chute is disposed at the front middle of the base, a detection mechanism is arranged in the sliding chute, the upper end of the base is fixedly connected to a first shell, the first shell is communicated with the sliding chute, the upper end of the first shell is fixedly connected to a second shell, a liquid storage cavity is disposed in the second shell, a spraying mechanism is fixedly connected in the liquid storage cavity, and the middle at the upper end of the second shell is fixedly connected to a first liquid conveying pipe. A cutting mechanism is arranged on a third shell, duringuse, vegetables are placed in a cutting box of the cutting mechanism, vegetables are cut up through a cutting wheel of the cutting mechanism, meanwhile, water is sprayed into the third shell through asecond micro water pump, juice on the surfaces of vegetable fragments is flushed away, then the water mixed with the juice enters the liquid storage cavity in the second shell and is stored, other cutting equipment and collecting container are not needed, and time and labor are saved.