Seasonal trends in infestation level of Bactrocera cucurbitae were analyzed to determine the factors that influence the infestation by melon fruit fly in the field and adoption of suitable insecticidal management on bottle gourd. The experiment was conducted during pre-kharif and kharif seasons in 2012 and 2013. Percentage of infestation was recorded on the basis of infested and total fruits. The highest fruit infestation i. e. 56.56 and 49% was recorded during 25th (17th June) and 24th (9th June) standard weeks during respective years. The correlation coefficient between per cent infestation by melon fly with weather parameters exhibited a significant positive correlation with maximum temperature and negative correlation with RH-I and RH-II. In case of management chlorphenapyr, acephate, spinosad and deltamethrin were most effective bio-rational insecticide for managing melon fly and provided higher yield.