Although substantial inquiry has been made into fitness levels of students, there has been scant examination of knowledge in this domain. This article seeks to review and analyze research on student health-related fitness (HRF) knowledge mastery in K–16 programs by examining studies published in the literature. Two major results emerging from the work are misconceptions about fitness and the lack of an adequate amount of HRF knowledge among students at all educational levels (i.e., elementary, secondary, and college). These results were essentially the same as those found more than 20 years ago, indicating a persistent deficiency in fitness education. In addition, little is understood as to how HRF knowledge contributes to the establishment of lifetime physical activity patterns. Student HRF knowledge determinants as well as effective instructional strategies also need thorough study. Based on these findings, implications for improving student HRF knowledge through physical education are discussed, and recommendations for future research are included.