Objectives : Since the laboratory medicine students have a special training course for improving their practical skills in different laboratories, it is necessary to pay more attention to this course to minimize the diagnostic errors committed by these students. The main objective of the present study was to evaluate the students' knowledge and practical skills to prevent and minimize the common diagnostic errors made by them. Method : In this descriptive cross-sectional study, the knowledge and practice of 75 laboratory students, who were passing the practical training course, were evaluated for the factors that might cause diagnostic errors in medical mycology laboratory. Results : The students' knowledge was better than their practical skills on factors that caused errors in diagnostic mycology laboratory. On the whole, 64.7% of the participants had good knowledge about factors that caused false positive and/or false negative results in direct microscopy. However, the rate of their practical skills was only 39.9% in this regard. In reporting the culture results, 65.35% of students had desirable knowledge about the false positive and false negative results, but only 46% of them had good practical skills in cultivation and reading the cultures. Overall, there was no statistically significant difference between the students' knowledge and practice with their sex (p = 0.073). Conclusion : Since there is currently an increasing trend in the prevalence of fungal opportunistic infections, accurate and prompt diagnosis can be very useful. It is important to have more inspection on the medical laboratory technology students' training course for accurate and useful courses.