The tourism competitiveness of the cities around the Beibu Gulf was studied using the entropy method from the perspective of the 14 indexes of tourism current competitiveness, tourism support competitiveness and tourism potential competitiveness. The results show that the cities of Sanya, Nanning and Haikou have the stronger competitiveness; the cities of Zhanjiang, Beihai, Chongzuo and Maoming have moderate competitiveness; and the cities of Yulin, Qinzhou, Yangjiang and Fangchenggang have the weak competitiveness. According to the analysis of the index weight and comprehensive ranking, almost each aspect contributes to the city competitiveness. The index weights of the tourism current competitiveness, tourism support competitiveness and tourism potential competitiveness are 0.272 22, 0.393 8 and 0.333 98, respectively. Based on the niche theory, the article put forwards the strategies: dislocation development, balanced development and regional tourism competition and cooperation development.