Primary Scientific Literature (PSL) significantly contributes to cultivating students' scientific literacy. However, students' visual strategies while reading PSL remain unclear. This study utilized eye-tracking technology to clarify students' visual attention allocation and fixation transactions during PSL reading, and explored their associations with students' self-reported reading strategy levels and reading outcomes. Thirty-eight undergraduate students majoring in biology (22 females and 16 males) participated in the study. They wore eye-tracking glasses while reading a PSL that included sections like abstract, introduction, methods, results, discussion, and reference. Participants also completed a Primary Scientific Literature Strategies Assessment and a post-reading exam. The study demonstrated that reading time and fixation count on the results page were positively correlated with self-reported PSL reading strategy scores and reading outcomes. The reading time and fixation count on the methods page are positively correlated with self-reported PSL reading strategy score. Moreover, the higher group showed significantly greater attention to results compared to the lower group. The higher group exhibited significant interaction between texts and figures in fixation transactions within the results, whereas this interaction was absent in the lower group. The research provided recommendations for educators to enhance students' PSL reading strategies and abilities.