Background: Nursing is a practice-based discipline with clinical practice being central to nursing education Therefore; preregistration education mission is to ensure that nursing students can meet quality and safety standards set for patient care. Unsafe students practice is described as a behavior that places the patient or staff in either physical or emotional jeopardy. Aim: to detect factors affecting safe clinical practices as perceived by students at technical nursing institute in Port-Said governorate. A descriptive comparative research design was utilized with a sample 166 students of technical nursing institute, (81 students) of the first and (85 students) of second year. Tool of data collection: A clinical safety practices of nursing students' questionnaire sheet was used. Results: concerning the effective level (60%=1.8), First year student have not reach it regarding any factor but second year students reach it regarding two factors which is the educational program and unsafe staff nurse`s practices. There was statistically significant relation between first and second year students regarding unsafe clinical nurse educator`s practices, unsafe nursing students –Clinical nursing educator relationship and The educational program at (p ≤ 0.05). Conclusion: More than half of first year students perceived the most effecting factor is unsafe clinical learning environment. In addition, more than half of second year students the most effecting factor is the educational program. Recommendations: Developing the educational program to pay an equal attention to the clinical practices and the theoretical knowledge.