The invention discloses a screening method for chemical risky substances of glucocorticoid in wash supplies. The method comprises the following steps: (1) establishing a precise quality database and a mass spectrum library of to-be-tested compounds; (2) pre-treatment and detection of an actual sample: performing pre-treatment steps of extraction, centrifugalization, purification, filtration and the like on a sample of the wash supplies, and performing ultrahigh pressure liquid chromatogram-quadrupole rod-electrostatic field orbitrap high resolution mass spectrum analysis and detection; and (3) comparing and analyzing the test result obtained in the step (2) with the precise quality database and the mass spectrum library established in the step (1) to screen the chemical risky substances of glucocorticoid in wash supplies. The screening method for chemical risky substances of glucocorticoid in wash supplies disclosed by the invention is high in accuracy, high in specificity and high in sensitivity, and is suitable for daily detection and quality control of the wash supplies.