In the United States, research on beginning science teachers provides little guidance regarding empirical minimum levels of discipline-specific science coursework for sufficient subject matter knowledge to teach science. Accordingly, in this study we analyzed secondary physical science teachers' science coursework for subject matter knowledge (SMK) and resulting misconceptions of chemistry and physics concepts. Findings were compared with state-level science teacher certification policies. Participants had either: (a) completed a master's level teacher preparation program with an undergraduate degree in science, (b) completed an undergraduate teacher preparation program with a minor degree or more in science, or (c) were undergraduate students enrolled in science courses required for chemistry and physics teacher certification. We analyzed participants' transcripts for discipline-specific science coursework credit hours and GPAs and identified possible predictors of SMK predictors of the likelihood of passing chemistry and physics misconceptions tests. We categorized teachers' level of SMK and used multiple variable and logistic regressions (n = 212 participants; n = 109 chemistry and n = 103 physics). To identify teacher candidates' possible misconceptions, we analyzed chemistry (n = 97) and physics (n = 91) participants' item responses with the corresponding science credit hours and GPAs. With increasing numbers of credit hours teachers held fewer misconceptions. However, even with medium to high SMK levels, teachers still held misconceptions about chemical bonding, electromagnetism, and Newton's laws until they reached critical credit hour and GPA thresholds. Lastly, we provide recommendations for physical science teachers' programs of study and state-level teaching certification policies, using empirical minimum quantity and quality of chemistry, physics, and mathematics coursework.