Intron length polymorphism (ILP) is a new type of PCR-based molecular markers with many advantages. We had previously developed 172 ILP markers in rice using the published genome sequence data of indica cultivar 93-11 and ja-ponica cultivar Nipponbare. In order to examine the reliability and the applicability of these ILP markers to genetic map-ping, we constructed a rice genetic map consisting of 172 ILP and 13 SSR markers with a total length of 1 905.7 cM using a BC1F1 (Nipponbare/93-11//Nipponbare) population. Comparison showed that the order of the markers in this map was ex-actly the same as their physical order, verifying the feasibility and efficiency of using ILP markers for genetic mapping. We also investigated the phenomenon of marker segregation distortion and found a region of serious segregation distortion in the short arm of chromosome 6.