According to policy documents and research studies, one key objective of science education is to develop students' inquiry abilities; however, relatively little is known about the interplay among students' inquiry abilities, the dimensions of their engagement, and their inquiry-related curiosity. The purpose of this study is to explore how four dimensions of engagement (i.e., cognitive, behavioral, emotional, and social) were driven by inquiry-related curiosity and how they affected the students' inquiry abilities. Structural equation modeling was employed to analyze data collected from 605 11th graders, including their responses to items in an online questionnaire and their performances on a computer-based assessment of scientific inquiry abilities. The results showed that students' curiosity was associated with their inquiry abilities, and such an association was partially mediated by the four dimensions of engagement in science laboratory classes. Moreover, the results revealed that among the four dimensions of engagement, only cognitive and emotional engagement had significant total effects on students' inquiry abilities and that the influence of behavioral and social engagement on inquiry abilities was completely mediated by cognitive engagement. This study suggests a critical role played by emotional engagement, cognitive engagement, and curiosity in developing students' inquiry abilities.