We observed visiting insects near cultivated roses (Rosa hybrida) including genotypes used to generate transgenic roses and wild roses (Rosa spp.) to clarify the possibility of gene flow under natural conditions. From May to July, pollen-gathering bees visited mainly rose species from 8:00 to 12:00 in the morning. The bees preferentially visited the rose species (R. rugosa, R. hirtula, R. bracteata and R. luciae), over the cultivated roses (R. 'Easy Going', R. 'Princess of Wales', R. 'L 'Aimant' and R. 'WGS'), probably due to the higher quantity of pollen produced and greater accessibility by the single-petaled wild species as compared to the double-petaled cultivated roses. Therefore, it seemed that cross-hybridization of rose species by the pollen of the cultivated roses is low under natural conditions. However, gene flow from R. 'Lavande' to R. spp. was possible given the high rate of honeybee visitation on R. 'Lavande'. On the other hand, in October, flies were observed on both wild roses (R. rugosa) and cultivated roses. However, the contribution of pollination between wild and cultivated roses by the flies seemed to be low due to their lower pollen carrying ability.