To assess the environmental risks of transgenic chili pepper with PepEST gene on non-target organisms before it exposes to the agro-ecosystem environments, we conducted the three sets of green peach aphids (Myzus persicae S.) life table experiment under laboratory conditions (Temp. 25℃, R.H. 50-70%, Photoperiod L16 : D8) in series during 2005-2006. We measured the net reproductive rate (R₀)*, the intrinsic rate of increase (r<SUB>m</SUB>), the mean generation time (T<SUB>c</SUB>), fecundity*, life span, and reproduction period between non-transgenic chili peppers and transgenic chili peppers, respectively. The life span of green peach aphids from three sets was 31, 27, 25 days, and the period of life span was similar to the general average length of green peach aphids, 25-29 days. Although the first reproduction of transgenic pepper was similar to the non transgenic pepper (P＞0.05), the fecundity and the net reproductive rate (R<SUB>o</SUB>) by using Jackknife method of transgenic pepper were lower than those of non transgenic pepper (P＜0.05). Conclusively, we observed the adverse effect from our results but we should execute further experiments to confirm the results at the fields with the similar way.