Cotton mealybug (Phenococcus solenopsisTinsley 1898) is one of the major sucking insect pest of cotton in Pakistan. This study was carried out during 2012 & 2013 in Multan District, Punjab, Pakistan to evaluate the response and conservation of biocontrol agents i.e. Aenasius bambawalei Hayat(= A. arizonensis Fallahzadeh, 2014) and Cryptolaemous montrouzieri Mulsant, 1850 against cotton mealybug (CMB). Biological responses of these biocontrol agents were assessed at different temperatures and humidity levels in the laboratory; which helped to design the rearing technologies for field releases. Data was collected at 100, 200 and 400 meters from NEFR surroundings after 07, 15 and 22 days of releases (DAR) of biocontrol agents. Results showed a significant decrease in CMB population; at 100 meter as 46%, 69% and 94% respectively; at 200 meter as 32%, 53% and 83% respectively; at 400 meter as 25%, 45% and 77% respectively. Cost benefit ratio of NEFR assessed was 1:1.8 and 1:3.2 when the crop losses reduced 20 to 50 percent in comparison with control field.