Mapping population was developed from the cross of TNlx GC9. The GC9 line possessed a dominant brown planthopper resistance gene. Phenotyping analyses were carried out in F3 generation, base on each of F2 individuals were judged for homozygous resistance, homozygous susceptible or iheterozygoussity. Bulk segregant SSR analyses were performed using 4-5 SSR polymorphic markers per chromosome. As a result, only the SSR markers of chromosome 4 seemed to co-segregate with the resistance gene in GC9 line. Afterwards, 76 SSR markers on chromosome 4 were analysed. Only 15 SSR markers were showed polymorphic on parents. Total of 224 F2 individuals of mapping population were surveyed. Linkage analyses were accomplished using MAPMAKER programme. It showed that BphZ locus located on short arm of rice chromosome 4, with the distance 25 cM, from the position of marker RM6997 is 62.2 cM to the position of marker RM17329 is 87.4 cM. Of which, the nearest markers were RM7051, RM3367, RM3839 Oocated in one side of resistance gene with the distance from 1.7 to 3.4 cM) and markers RM1388, RM1223, RM17235 (located in other side of resistance gene with the distance from 1.7 to 3.2 cM). These markers can be applied into rice breeding for brown planthopper resistance.