Over the course of summer of 2010, I conducted a study in Mnazi Bay Marine Park in the South Eastern Tanzania (East Africa) with the generous support from the Compton Foundation. I chose this marine park because it is new and not much been explored in its impacts on the local communities; itranks among the highest in marine biodiversity; and the impacts of marine parks on the livelihood of local people are still debatable. Specifically, I was interested in answering two questions: the extent to which creation of this marine park has influenced the livelihood of the local communities, and the extent to which the creation of this marine park has changed the perception of the local people towards the marine park. To answer the two research questions, I conducted this study in six villages; five of the six villages are located in the marine park while the other village is located in the buffer zone. Village selection was based on particular characteristics of each village such as dependency on fisheries and conflict occurrence. Several social research methods were involved in order to answer the questions. Questionnaires, focus group discussion, participant observation and interviews with the park officials were used as sources of primary data. The questionnaires had both open ended and closed ended questions. A total of 160 semi-structured interviews were conducted in four villages, 40 in each village, with the heads of households. The information collected was analyzed both qualitatively and quantitatively. Results indicate that the marine park creation has significantly affected the livelihood strategies (fisheries and agriculture) of the communities. However, both livelihood strategies showed no disparity with village location, which indicates that they both form essential livelihood strategies for all villages. As a result of negative impacts on livelihoods, people have significantly changed their attitudes toward fishing. People in the seafront villages are more likely to have changed attitudes towards fishing than people in inland villages. The failure of the park to deliver promises made during implementation of the park, and the information gap that exists between villagers and the park are the major drivers of these outcomes.