This study aims to explore whether there is a statistically significant difference in pre-service teachers' perceptions of professional ethics in teaching according to gender, major and academic achievement. The data was collected from 541 conveniently sampled pre-service teachers from seven different majors and four state universities using a 43-item scale developed by the researchers. The data was analyzed using Linear Regression Analysis in R. The results indicated that gender was a significant predictor of pre-service teachers' perceptions of professional ethics in teaching, and that females held significantly more ethical perceptions about the teaching profession compared to the males. The results also indicated that pre-service teachers' majors did not seem to have a significant effect on their ethical perceptions about the teaching profession with the sole exception of classroom teaching. The results further revealed that academic achievement was not a significant predictor of pre-service teachers' perceptions about their profession. However, when gender was used as a covariate, the analysis indicated that teachers' majors were a significant predictor of pre-service teachers' perceptions of professional ethics in teaching. The results further indicated that academic achievement was not a significant predictor of pre-service teachers' perceptions about their profession even when the pre-service teachers' gender and major were controlled.