To survey the effects of flooding during the reproductive growth stages of aerenchyma formation and ethylene production in soybean cultivar DPX experiment the completely randomized factorial was in 2012 in Gorgan University of Agricultural Sciences and Natural Resources. Factors examined include nutrition levels in three levels (1 - inoculated with bacteria JaponicumBradyRhizobium 2 - non-inoculated plus nitrogen fertilizer (urea) 3 - non-inoculated without nitrogen fertilizer) and the second factor is the duration ofwaterlogging stress (0, 5, 10 and 15 days). Based on the results obtained with increasing duration of flooding stress on the plant, ethylene production increases. The slope was slowly at first and then increases exponentially. Among the nutritional treatment of ethylene production , non-inoculated plus nitrogen treatments was higher than the other two treatments, and the non-inoculated treatments without fertilizer lowest ethylene production was observed. Images of cross sections of soybean plants showed that the stress increases with the duration of flooding stress signsaerenchyma tissue formation was observed in soybean plants. 15 days of flooding treatment aerenchyma tissue formation was observed at all levels of nutrition.