The invention relates to a hybridoma cell strain AB1 and a 2,4,5-trichlorophenoxy acetic acid monoclonal antibody generated thereby and belongs to the technical field of food safety detection. The invention relates to the hybridoma cell strain AB1 of the 2,4,5-trichlorophenoxy acetic acid monoclonal antibody. The cell strain is preserved in CGMCC with the preservation number of CGMCC No.13083. The monoclonal antibody secreted by the cell strain has relatively good specificity and detecting sensitivity (IC50 value is 4.4ng/mL) on 2,4,5-trichlorophenoxy acetic acid, can realize analysis and detection on residual 2,4,5-trichlorophenoxy acetic acid in an agricultural product, provides a raw material for immunodetection of residual 2,4,5-trichlorophenoxy acetic acid in food, and has actual application value.