Abstract:We have studied the genetic diversity of 68 sugarcane (Saccharum spp.) germplasms imported from Australia (Q), France(FR), the United States(CP) and Philippines(VMC) and stored in the National Sugarcane Germplasm Resources Garden by taking the amplified fragment length polymorphism(AFLP) marker technique. The result shows that the genetic similarity coefficient(GS) among 68 sugarcane germplasms is quite high, ranging from 0.497 5 to 0.887 9 with a mean value of 0.761 2, indicating that most of them have a close relationship with each oyher and a similar genetic base with each other, that there is no enough rich genetic diversity among 68 sugarcane germplasms. The order of the average GS coefficient is VMC(0.825), Q(0.802), CP(0.752) and FR(0.685) successively. The analysis by UPGMA indicates that the 68 foreign sugarcane germplasms can be divided into 5 groups (A–E) at a GS coefficient of 0.676. CP67–412, FR94–515, FR96–626 and FR94–126 belonged to group A–D respectively. The rest(64 sugarcane germplasms) fall in the group E, covering a percentage of 94.1% of all the germplasms. CP67–412, FR94–515, FR96–626 and FR94–126 in Group A–D show a distant relative relationship and a special genetic composition, compared with the others. The study has found that the FR germplasms are more divergent and embody more genetic information than the others. .