The cricket species Modicogryllus confirmatus Walker displays distinct wing dimorphism. In this paper, effects of photoperiod, temperature, density, and heritability on wing differentiation in a subtropical population of M. confirmatus were studied in order to find out possible relationship between wing development and environmental and genetic factors. The results showed that neither constant photoperiod nor changing photoperiod could influence its wing differentiation. The macropterous rate did not change significantly when nymphs were reared under 25 ℃ and 30 ℃, but it decreased significantly when nymphs were kept under exceeding high temperature (35 ℃). These results indicate that seasonal adaption may not be the reason of wing differentiation of M. confirmatus, but high temperature stress may have a strong micropters inducing effect. The macropterous rate also did not change significantly when nymphs were kept under different density suggesting the density could not affect the wing differentiation too. After selection for 3 generations the frequency of micropters in a SW selected line increased significantly, whereas it remained at a low level in a LW selected line. Crossing experiments indicated that wing morph was under polygenetic control.