Eleven evaluation factors from four aspects, namely, resources, environment, economy, and location are selected in this study. Principal component analysis and geographic information system (GIS) technology are used to examine the spatial distribution characteristics of sea area suitability for tourism and recreation from the grid scale. Results show that the principal component analysis method can 1) extract four potential comprehensive indexes (i.e., principal components) by comprehensively analyzing the information of numerous influencing factors of sea area suitability for tourism and recreation, 2) calculate the comprehensive score by using the principal component information, and 3) evaluate sea area suitability for tourism and recreation. The evaluation results can provide reference and support for not only the selection of sea area for tourism and recreation but also the rationality demonstration of marine projects.