Guided by the notion of academic momentum, this study drew data from longitudinal transcript records at a large public 4-year research university and examined factors that specifically contribute to community college transfer students' academic momentum. It also explored how early academic momentum along with students' sociodemographic characteristics impact degree attainment in science, technology, engineering, and mathematics (STEM) fields of study. This study conducted multinomial logistic regression analysis and found that certain students' background characteristics (i.e., gender, age, and family income), community college academic achievement (i.e., associate degree completion, and number of community college credits accepted), and early academic performance at the 4-year university (math and English preparedness, number of credit hours attempted, and first-semester grade point average) were significantly related to transfer students' likelihood of obtaining a STEM degree. The findings provide new knowledge about academic momentum and could be used to enhance the community college pathway to STEM degree completion.