Ocean sustainability and resource use are emphasized globally. The primary goal of ocean preservation is to enhance citizens’ ocean literacy. In this study, cluster sampling was conducted on students from seven public middle schools in Taiwan to investigate their use of ocean literacy concept words, propositional sentences, and knowledge sources. Qualitative analysis, descriptive statistics, and one-way analysis of variance were conducted on 496 valid questionnaires. The middle school students exhibited an accuracy rate of 63% for ocean literacy sentence-making, which indicated a basic level of performance. The students commonly used terms such as “ocean,” “Atlantic Ocean,” and “tsunami.” Students had common misconceptions when using the terms “sea level rising,” “Kuroshio current,” and “tsunami.” In addition, students who were female, in a higher grade, and who attended a coastal school had higher ocean literacy scores. The students’ primary sources of ocean literacy knowledge were museums and television. Through an analysis students’ use of ocean concept words and misconceptions, the aim of this study was to enhance the implementation efficiency of marine education to cultivate students’ ocean literacy.