When freshly laid eggs of Corcyra cephalonica were exposed to 20, 40, 80 or 160 µl volume of Callistemon lanceolatus oil volatiles for 6 or 12 hour duration a significant reduction in percent egg hatchability was recorded only with 80 or 160 µl volume of the oil. When exposure period were increased up to 24, 48 or 72 hour a highly significant reduction in percent egg hatchability was observed at 40, 80 or 160 µl of the oil. The reproductive potential of C. cephalonica was affected variably when new born larvae of this pest were reared in a programmed manner with 20, 40, 80 or160 µl oil volatiles of C. lanceolatus. When freshly emerged male and female was exposed to C. lanceolatus oil volatiles emanating from 20, 40, 80 or 160 µl for 3 hours, there was increase, though not significant, in egg output and egg hatchability of breeding pairs. But when exposure period was increased up to 6 hour there was a significant decreased in reproductive potential of breeding pairs. A significant reduction in Glycogen level, Total lipids, Total protein and Total free amino acids level was recorded in the testes and ovaries of adult moths exposed to oil volatiles action of Callistemon lanceolatus, for 6 hours emanating from 20, 40, 80 or 160 µl volume of this oil.