We studied in this research the systemic activity of fungicide carbendazim in cucumber plants (Hybrid F1 Milton). The soil was treated with fungicide with concentrations of 0.25 - 0.5 - 1.0 - 2.5 g active ingredient per kg of soil and the month-old plants was sprayed (three true leaves) with the recommended concentration 0.25 active ingredient per liter of water, half and double of concentration. Bioassay method was used to detection the systemic activity of fungicide by putting the plant parts in direct contact with sensitive fungus spores within petri dishes that containing PDA. It has been detected the presence of carbendazim in the root , cotyledonary leaves and first real leaf after 20 days from treatment the soil for all concentrations, as it was observed the fungicide persistence in plants after forty days. In the spraying treatment, It has been detected the presence of carbendazim after one day for all concentrations and for the recommended and double concentration only after five, ten and twenty days of spraying.