Abstract: In order to study the temporal change of extra-genes express in rice, the activities of chitinase and β-1,3-glucanase in the leaves of the four transgenic rice lines with extra anti-fungal genes (chitinase gene and β-1,3-glucanase gene) in different growth period were measured using enzymatic reaction combined 3,5-dinitrosalicyclic acid (DNS) colorimetry method. The results showed that the activities of chitinase and β-1,3-glucanase in both transgenic rice lines and their parents increased with the proceeding of growth period. In the early growth period, there are slight difference of enzyme activities between transgenic rice lines and their parents, whereas the difference became greater with plant growth, which suggested that, in early growth period, there are low extra-genes express, even gene silencing or gene suppression. The curves of enzyme activities in transgenic lines vary greater than parents, and there are no correlation between enzyme activities and the number of extra gene. It was concluded that, for extra-gene express, there were time efficiency but no numerical superiority.