Objective To study faunal characteristic of flea in Liaoning province. Methods Field collection and supplement literature, investigation on flea in different natural geographic regions in Liaoning province during 2008-2015, the collected flea specimens were systematically classified. Using the principles and methods of animal geography and physical geography to study the distribution of fleas in different animal geography areas in Liaoning province. Results In total 47 species, 6 families 23 genera of fleas were found in Liaoning province, of which 19 species of grassland fleas, 17 species of forest fleas, 6 species of worldwide distribution, and 5 species of local distribution. In the distribution of the world flora, and 16 species shared with Oriental world the most common and the most closely related, followed by the new North sector of 9 species. And all the other groups of fleas were worldwide species, the relationship was distant. There are 46 species of fleas in Northeast Asia, 42 species of subcontinent in Central Asia, 35 species of Siberian subfamily, 9 species of subcontinent in Asia and 7 species of subcontinent in suburbs. Therefore, Liaoning and Siberia shared, the largest number of fleas and the most closely related, followed by the European sub-community, and the Mediterranean Asia with less connection; there are 41 species of flea, 42 species in North China, 38 species of Mengxin district, 15 species of Qinghai-Tibet area, 15 species of central area, 10 species of southwest area and 9 species in southern China. Conclusion Fleas, like other natural elements, are an integral part of the environment, the distribution of fleas in each animal's geographical area is the result of adaptation to the natural geographical environment.