This work was conducted to evaluate the molluscicidal activity of Kz mineral oil compared to methomyl insecticide against one of the most serious land snails; white garden snail Theba pisana under laboratory conditions. The toxicity changes in juveniles and adults of T. pisana snail treated with three concentrations (1.25, 2.5 and 5 %) for Kz oil and (0.031, 0.063 and 0.125 %) for methomyl were evaluated using dipping technique of lettuce and cabbage leaves.  Results indicated that the tested concentrations of Kz oil had toxic effect on both juveniles and adults increasing with time passage and concentration. The highest mortality percentage obtained with Kz (5%) recorded (53.33 %) and (46.67 %) for juveniles & adults with lettuce leaves, respectively however the same concentration gave (40%) and (26.67%) mortality for juveniles & adults with cabbage leaves, respectively after three weeks post treatment. Regarding to methomyl pesticides, the toxicity effect increased also by time passage and concentration where the highest mortality in both juveniles & adults recorded (66.67% & 46.67 %), respectively when lettuce leaves are dipped in 0.125 % methomyl. Treatment with all concentrations of Kz oil and methomyl exhibited remarkable reduction in amylase and invertase activities compared to control. Furthermore, Kz oil showed very low toxic effect to adults of Apis mellifera by feeding whereas, toxicity was almost non- exist when bees were in contact with treated leaves.