Chromosome numbers and morphology of 4 genera of Liliaceae (s.str.) from Hengduan Mountains of southwestern China were studied. Almost all populations in Lilium were diploid, with 2n=24, except that populations of L.tigrinum were found triploid, with 2n=36. All taxa in Fritillaria investigated were diploid, with 2n=24 and the secondary constrictions were obvious and abundant. Diploid and triploid exist in different populations of Notholirion bulbuliferum, with 2n=24 and 2n=36, and there was one population contained both ploidy types. For Lloydia, only one taxon Lloydia tibetica was studied, with 2n=23. All taxa studied were collected in Hengduan Mountains, and the differences among these genera were obvious, which would contribute to the future taxonomic study. The karyotypes of L.matangense and Lloydia tibetica were documented for the first time.