Ametryn, diuron and oxyfluorfen at the recommended rates were applied to a drip-irrigated banana field. Soil samples were collected from treated plots 1, 2, 4 and 8 months after initial application. The persistence of these herbicides in soil was measured on the basis of dry weight production of cucumber plants. The results showed that dry weight of cucumbers was significantly lower in soil sampled 1 month after the diuron treatment. However, there were no significant dry weight reductions when cucumbers were grown on soil sampled 1 month after ametryn and oxyfluorfen treatments. Neither did any dry weight reductions occur when these plants were grown on soil sampled 2, 4 and 8 months after all three herbicide treatments. The order of herbicide persistence in soil is established as diuron> ametryn> oxyfluorfen. The short persistence of these three herbicides in a drip-irrigation banana field is thus confirmed on the basis of results of this study.