Abstract: Chromosomes of 20 species of tropical fruit trees in South China were stu died. The results are as follows:1. 2n = 18 = 6m + 10sm + 2st for Hodgsonia macrocarpa Cogn.2. 2n = 30 = 10m(2SAT)+ 10sm + 4st + 6t for Litchi chinensis Sonn.3. 2n = 30 = 16m + 8sm + 4st + 2t for Euphoria longana Lam.4. 2n = 18 = 12m + 6sm for Clausena lansium(Lour.)Skeels5. 2n = 22 for Psidium guajava L.6. 2n = 34 for Eriobotrya japonica Lindl.7. 2n = 33 = 18m + 15sm for Musa paradisiaca L.8. 2n = 50 for Ananas comosus Merr.9. 2n = 56 for Artocarpus heteropkyllus Lam.10,11. 2n = 48 for both Canarium album(Lour.)Raeusch. and C. pimela Koenig12. 2n = 40 = 20m + 18sm(SAT)+2st for Mangifera indica L.13. 2n = 30 for Diospyros discolor Willd.14. 2n = 34 for Cydonia oblonga Mill.15. 2n = 44 for Syzygium jambos(L.)Alston16. 2n = 18 for Carica papaya L.17. 2n = 18 = 18m for Annona squamosa L.18. 2n = 22 = 12m + 10sm for the wild banana in Guangdong(Musa sp.)19. 2n = 22 = 18m(2SAT)+4sm for the wild banana in Xishuangbanna, Yunnan(Musa sp.)20. 2n = 24 = 22m + 2sm for Persea americana Mill.