In this study, effects of blue and black polyethylene mulches used together with drip irrigation on yield of Yağmur cucumber cultivar were investigated under greenhouse conditions and mulching treatments were compared with unmulched drip irrigation treatments. Experiments were conducted in a polycarbonate greenhouse in Kayseri province of Turkey in 2019. Throughout the growing season, 655 mm irrigation water was applied in drip+mulch treatments and 776 mm in unmulched drip irrigation treatments. Although 16% less water was applied in drip+mulch treatments, 37% more yield was obtained from drip+blue mulch treatments and 34% more from drip+black mulch treatments. The highest cucumber yields per decare (12296.7 and 11783.6 kg) were respectively obtained from drip+blue mulch and drip+black mulch treatments and the lowest (7771 kg) from unmulched drip irrigation treatments. The highest weed dry biomass (88.42 g m-2) was obtained from unmulched drip irrigation treatments. While the effects of mulching treatments on weed biomass were found to be significant as compared to unmulched treatments, blue and black mulches were not significantly different.