Ocean literacy is of particular importance to an island nation like Taiwan. In this study, a Chinese version testing tool for ocean literacy was developed specifically for senior high students in Taiwan. The ocean literacy inventory can be administered using a group test format and consists of the following seven subscales: features of ocean, ocean and its life shape earth, weather and climate, earth habitable, diversity of life and ecosystems, ocean and humans are interconnected, and ocean largely unexplored. In this study, a valid sample consisting of 1,027 participants was collected and various psychometric assessments including Cronbach's alpha, the multitrait-multimethod matrix (MTMM), confirmatory factor analysis (CFA), Multiple Indicators Multiple Causes (MIMIC), and multiple-group CFA were performed to test the reliability and validity of the tests. The results of the various analyses confirmed that the ocean literacy inventory met the requirements for standardized tests. A conversion table that listed the raw scores, standardized Z scores, and cumulative percentages for the various subscales and the full test was also compiled, so as to provide a quick reference for future users who will be using the inventory to assess ocean literacy ability.