Abstract: Background and Objectives :  Professional ethics is part of midwifery skills that cannot be separated from it .Midwives must get acquainted with this skill and ethical laws, avoiding at the same time unethical manners. Materials and Methods : This study was cross-sectional survey which examined knowledge and attitude of 101 midwives that had been selected by convenient sampling procedure working hospitals of Mashhad. A questionnaire was used in order to collect data. Its validity and reliability was tested and established based on a sample of 20 midwives. The level of knowledge was divided into three groups: good (0.6-1), moderate (0.3-0.5), and weak (0-0.2). Results :  The results showed that the midwives' knowledge of gynecologic laws and professional rules was not sufficient and most of midwives had positive attitude (60.8%) but variables such as age, level of education, duration of work, work place, etc. didn't have any effect on their knowledge and attitude. In addition, data analysis didn’t show any statistical relation between attitude and knowledge of midwives.