Materials 9507, 9517 and their BC1, BC2, F1, F2 and so on 6 generations were carried under low-temperature treatments， 12/8℃ in day/night, with 7.5 h everyday by the light intensity of 30μmol/m2·s (or 2000 lx) for 14 days，which were difference in tolerance of low temperature and weak light. The dominat and additive effects of chilling tolerance was researched by the major gene - polygenes inheritance model，and the genetic parameters were estimated. The results indicated that the chilling tolerance index was controlled by 2 pairs of additive major genes plus additive - dominance polygenes, and the average of chilling tolerance index of F1 was higher than midparent value. The heritability of major gene was 62.871~79.310%, the heritability of polygenes was 3.448~7.792%, and the heritability of major gene plus polygenes was 74.026~82.759%.In other words under the low temperature condition, the environment plays a very little role for the chilling tolerance in Cucumis sativus L., which is suitable for being chosen in the early generation .