The effects of ethephon (2,chloroethyl-phosphonic acid), ancymidol [α-cyclopropyl-α-(4-methoxyphenyl)-4-pyrimidinemethanol], DPX1840 [3,3a-dihydro-2-(p-methoxyphenyl)-8H-pyrazolo(5,1-a)isoindol-8-one], Uni-P293 (2,3-dihydro-5-6-diphenyl-1,4-oxathiin), and morphactins and their interaction with GA (gibberellic acid) on the translocation of 2,4,5-T (2,4,5-trichlorophenoxacetic acid) in bean (Phaseolus vulgaris L. ‘Stringless Green-Pod’) seedlings were determined. The growth retardants and GA were either applied as foliar treatments or injected at the cotyledonary node with 2,4,5-T. Foliar pretreatment of bean seedlings with ethephon and ancymidol 2 days before 2,4,5-T treatment inhibited 2,4,5-T translocation to young shoots but did not affect basipetal translocation greatly. These effects were reversed by foliar application of GA 1 day before 2,4,5-T injection. Foliar pretreatment of bean seedlings with DPX 1840 2 days before 2,4,5-T treatment increased 2,4,5-T translocation to young shoots and inhibited basipetal translocation. The effects of DPX1840 were not reversed by GA treatment. When ancymidol, DPX 1840, and morphactins were injected into the stem tissue with 2,4,5-T the acropetal translocation of 2,4,5-T increased and basipetal translocation was decreased by DPX1840 and morphactins. These effects were not reversed by the simultaneous GA injection. Uni-P293 had little effect on 2,4,5-T translocation. Growth retardants other than Uni-P293 appear to inhibit basipetal 2,4,5-T translocation directly. Ethephon and ancymidol may have secondary effects on 2,4,5-T translocation that can be reversed by GA treatment.