Zucchini / Summer squash (Cucurbita pepo L., 2n=2x= 40), an economically important member of the gourd family, Cucurbitaceae. Trial was conducted in factorial Randomized block design with three planting dates and four different spacing during the kharif season of 2018-19, at Horticulture Research Field, SHUATS, Prayagraj, UP. While observing the effect of planting dates, highest vegetative growth & highest number of female flowers was recorded in D3 (21th September) whereas, lowest sex ratio was in D2 (06th September). Among highest number of fruits per plant, fruit yield per plant, yield per plot and yield per hectare was recorded in D1 (21th August). Among various spacing S4 (90 x 150cm) noticed significantly highest vegetative growth and highest number of fruits per plant. Whereas, highest number of female flowers, lowest sex ratio, fruit yield per plant, yield per plot and yield per hectare was recorded in S2 (70 x 90cm). From the present investigation, it is concluded that early planting (D1 22nd August) combined with plant spacing S2 (70 x 90 cm) of zucchini performed better in terms of growth, yield and physical quality. Therefore, it is concluded that combination of treatment S2 D2 (70 x 90 cm, 6th September) had the best B:C ratio of 3.79 for the production of zucchini.