The impacts of tourism have been given much attention by scholars attempting to examine the perceptions as well as attitudes of the local residents toward tourism. Such studies have been carried out thoroughly in the context of the developed countries. However, very little research has been carried out in developing countries. This study attempts to make a little contribution to the sustainable development of tourism by examining the residents' profile, perceptions and attitudes towards tourism impacts and tourism development in Ha Long Bay, the Vietnam's first World Heritage Site (recognized in 1994). Data were collected by means of a questionnaire study. Based on 417 respondents surveyed, the findings show that the majority of respondents were young, Kinh rather than other ethnic group, they were married and were living in Ha Long Bay for over 20 years. On the whole, respondents viewed tourism positively and would support tourism development. They were generally in favor of tourism that contributes economically and socio-culturally to Ha Long Bay. They were, however, slightly ambivalent to environmental impacts of tourism. Implications, policy recommendations and limitations of study are presented in the conclusion.