Abstract: Microshoots of sugarcane cultivar ROC22 were used to study root occurrence and changes in the contents of IAA, ZR and ABA and the activities of POD in the course of root development from root primordial induction to root elongation after those microshoots without root system have been transplanted in the green house. The results showed that the root germination occurred at 4~6 d, and 80% of plantlets were observed visible roots at 6 d. The contents of IAA, ZR and ABA increased at root primordia-induction(0~2 d), decreased and kept at low level at root primordial formation (2~4 d) and increased before and after root germination (4~8 d). The activity of POD decreased at root primordial induction, fluctuated from minimum point to maximum point at root primordial formation, decreased before root germination and kept at low and stable level during root elongation.