Many Liberian teachers have limited experiences and low efficacy for teaching science, technology, engineering, and mathematics (STEM), which results in students receiving little preparation and having low levels of motivation to pursue STEM careers in Liberia. Teacher attitudes are central for efficient teaching STEM. However, little is known about the attitudes of teachers towards STEM education, as well as what factors influence these attitudes among Liberian teachers. This paper describes a novel study on Liberian science teachers' attitudes, and it seeks to elucidate and comprehend the current attitudes toward STEM education among science teachers and identify the factors that might influence these attitudes. A questionnaire was developed to examine attitudes towards STEM education among 194 in-service science teachers and was reinforced by interviews with 10 science teachers. A significant difference was observed between private- and public-school science teachers with respect to their overall attitude scores. A marginally significant difference was found among teachers from different grades. Findings from regression analysis showed that professional and administrative support, peer collaboration, STEM training, and teaching time positively influence science teachers' attitudes towards STEM education. Recommendations regarding how to support these teachers were also provided based on the analysis of interview data.