This study aimed to determine the relationship of factors inﬂuencing bioethical convictions of B.S. Biology students. It focused on the efficacy of case study discussion in improving comprehension of the four Bioethics principles, the efficiency of a Bioethics course in improving bioethical convictions, the identifying predictors for comprehension of Bioethics principles and bioethical convictions, and the creating of model constructs of predictors which are ft for the data. The convictions test for bioethical issues, Comprehension test for the four bioethics principles, a survey-questionnaire, Otis-Lennon School Ability test and 16PF test were used in gathering data from 116 participants. T-test for dependent samples was used to determine effects of the case study discussion and the bioethics course. To identify predictors for comprehension and convictions among personal and family background factors, global and primary personality factors, and mental ability, step-wise multiple regressions was utilized. Path analysis models were then constructed and tested for goodness of ft using Structural Equation Modeling (SEM). Results showed that case study discussion and the Bioethics course were effective in improving comprehension and bioethical convictions, respectively. Predictors for comprehension of Bioethics principles before case study discussion were verbal ability, warmth, and exposure to media. Sex and openness to change were predictors for pre-convictions. Post conviction predictors were anxiety, self-control, extraversion, liveliness, and perfectionism. Four corrected path models were accepted based on ft indices criteria of SEM. In conclusion, personal factors, much as sex and personality factors are contributors in bioethical convictions, and not cognitive factors like mental ability or comprehension of the four Bioethics principles.