Immigrant settling for many years may be so strongly influenced by local culture that we cannot tell their descendants apart easily from natives, according to some characteristic of social behav-ior and folk customs. But some residual ingredients of spoken language and basic vocabulary former im-migrant often used have been inherited and still have been using today, which can help us trace back the im migrant's descent and get to know the laws of spreading and diffusion of culture. As a latish cul-ture- developed island far away from mainland, its culture of Hainan Island have strong outer language-orientated peculiarity. That is, the culture of Hainan Island is a kind of distinct cultural that integrated highly, which is on the basis of a native background culture called as "li culture", took in a lot of nut-ritive value from mamy other peculiar culture, such as "han culture", "miao culture", "zhuang cul-ture", " hui culture", and modern culture developed by overseas Chinese, agricultural reclai mation cul-ture, western culture etc. as well. In this paper, we can know that Hainan Culture is one kind of frontier pioneering cultures which is a outcome of Hainan's peroidic developments. And we find out the truth that the present Hainan dialects result from the continuous spreading and diffusion of frontier pi-oneering cultures in the couse of Hainan development, by aalyzing the peculiarity and distribution of Hainan dialects, and by studying spreading and diffusion of Hainan culture, by tracing out the devel-opment and evolution of Hainan culture. All these help us analyses the function of verification to the spreading and diffusion of frontier pioneering culture by dialect. That is to say, practicality of a special kind of culture and its propaganda often have decisive influence on cultural spreading and inheritance. These dialects emerging in a place become popular regionally and a distinctly directive sign, which is enough to deafly indicate characterisics of im migrant activity. Dialect is a mirror of im migrant history and the latter is a source of dialect. We can sort out clear line of transplantation and evolution and forming of Hainan dialects, on the basis of studying the dialect family-tree, which help us understand the interrelationship between immigration in the course of developing frontier areas and current dia-lects.