Background: Clinical teaching is an important component of clinical education. In nursing, clinical teaching is ensured by clinical nurse educators. The quality of the student-teacher interaction in the clinical field can either facilitate or hinder the students' integration of theory to practice. The study aimed to assess the effect of training program on clinical teaching skills of the clinical instructors at faculty of nursing, Suez Canal University. Design: A quasi-experimental study design. Setting: this study was conducted in three settings as follows: Faculty of nursing SCU, Suez Canal university hospitals and Ismailia general hospital. Sample: Convenient sample were included all clinical instructors (43) who participate in students' clinical teaching during the academic years 2016/2017 and 2017/2018.Tools: Tool (1): Self-Need Assessment Sheet which included two parts. Part I: personnel data of clinical instructors, Part II: it contains question about the needs related to clinical teaching skills. Tool (2): clinical teaching skills observational checklist. Results: There was a statistically significant improvement between mean scores of clinical instructors in relation to their skills at pre, post and follow up. Mean score at pre-program was (46.6±4.62) which increased at post program (82.4±2.8) and slightly declined at follow-up to (82.1±2.93). Conclusion: the clinical teaching skills of clinical instructors improved post and follow up implementation of the program compared to pre implementation of the program. Recommendations: Ongoing professional education for clinical instructors about clinical teaching skills and a clinical teaching efficacy scale must be developed to evaluate clinical nursing instructors based on the attributes of rules and their capabilities.