This study examined whether an individual’s self-efficacy has a moderating role in the relationship between the different types of recycling/reuse knowledge they may have and their recycling/reuse intention, and the positive relationship between recycling/reuse intention and recycling/reuse behavior. A total of 725 undergraduate and graduate university students were recruited to complete an online survey via MTurk, with the survey covering topics such as recycling/reuse knowledge, intention, behavior, and self-efficacy. Five hypotheses were tested via structural equation modeling. The results showed that even with low self-efficacy, acquiring “effectiveness” recycling/reuse knowledge can enhance recycling/reuse intention and behavior. Conversely, the respondents with high self-efficacy were shown to have positive recycling/reuse intentions and behaviors due to their “social” recycling/reuse knowledge. In general, recycling/reuse intention and behavior were positively related. These significant findings imply that educators, environmental agencies, and brand managers must develop efficient education and/or advertising strategies to provide appropriate action-related recycling/reuse knowledge (including both effectiveness and social knowledge) to university students with either low or high self-efficacy in order to enhance recycling/reuse intention and, ultimately, behavior.