The purpose of this descriptive research study was to investigate the effect of teaching efficacy on clinical practice education of small and medium-sized hospital nurses and to provide basic data for improvement of clinical practice education. The study was conducted from April 15th to April 30th, 2017 with 121 enrolled nurses working in small hospitals in K city. SPSS was used to analyze the data and Pearson's correlation coefficients, t-tests and multiple regression analysis were conducted. The different sub domains of teaching efficacy were significantly positively correlated with confidence in knowledge of their own major, reduction in class strategies, and leadership to students if the nurses are older than 40 years, have a clinical career of more than 10 years, and are above chief nurses (p <.001). Finally, factors affecting teaching efficacy included the hospital atmosphere, relationship with the clinical leaders, and job satisfaction. Clinical practice education should be improved through the development and application of a systematic teaching program that can improve nurse teaching efficacy as a clinical practitioner.