The terrestrial snail became economic serious pests attacking field corps, vegetables and orchards. This work was aimed to study the effect of some environmental factors on the biology of two species of land snails, Monacha obstructa and Eobania vermiculata. Results showed that, the soil types were markedly effective on fecundity and Ovipostion period of the land snails, M. obstructa and E. vermiculata. Clay and sandy loamy soils were favorable to such snail species, Whereas the general means of total clutches and eggs laid by one pair of both snails during the entire breeding season were (6.4 and 5.4 clutches and 211.4 and 271.6 eggs) and (6.36 and 6.36 clutches and 250.02 and 273.36 eggs) for M. obstructa and E. vermiculata respectively. While the highest values of general means of clutch size were (50.29 and 42.94) for sandy loamy soil while, the highest oviposition period were recorded in clay soil with values (69.4 and 68 days) for the two land snails respectively. Also, soil moisture was effected on number of per clutch. The highest egg number were recorded at percentage 80% soil moisture (116.8 eggs for M.obstructa) and (89.67 eggs for E. vermiculata) On the other hand, data revealed that the eggs of the two species of snails did not hatch at 30°C. On other hand, the highest values of egg hatch were found at 15°C with values 81and 76% for M. obstructa and E, vermiculata respectively. As the temperature increased, the egg hatching was significantly decreased. It clear that eggs of snails are sensitive to high temperature and embryos died at 30°C.