As scientific literacy plays a contributing role in identifying, analysing, and solving environmental matters that our world is facing, there is growing consensus to mandate environmental matters in science classrooms following five decades of efforts in promoting environmental education. However, much remains unknown about the relationship between students’ awareness of environmental matters and their science literacy scores on standardised test. Using data drawn from the 2015 Program for International Student Assessment (PISA) science performance assessment, this study investigates the relationship between students’ awareness of environmental matters and their science literacy scores in the context of established predictors for science learning. In all the regions’ multilevel models ranging from medium to large effect sizes, a significant and positive relationship emerges between students’ awareness of environmental matters and science literacy scores. Among the well-known predictors for science learning, student science self-efficacy associates positively with student science literacy scores across the regions. In contrast, inquiry-based science instruction associates negatively with the scores. Except for these two well-known predictors, variations exist in the relationships between other variables among the regions. Given all the regions’ evidence showing the positive linkage between students’ awareness of environmental matters and science literacy scores, the present study signifies the importance of integrating environmental issues into traditional science classrooms, suggesting that there should be systematic supports that enable both environmental and science educators to collaborate towards the development of an interdisciplinary environmental science curriculum.