Background: Regardless of their convenience, medical abbreviations have been responsible for serious errors and deaths. Look-alike abbreviations or symbols, throughout the healthcare literature, are widespread examples of common errors. These problems involve numbers as well as letters. Objectives: To identify used abbreviations in medical records in surgical departments in El-demerdash hospital and to assess comprehension level of abbreviations written in medical records by medical and paramedical staff. Material and methods: A cross sectional study was done to review 400 medical records in surgical departments in El-demerdash hospital for identification of used abbreviations. Three hundred healthcare professionals in Eldemerdash hospital were inquired to identify the meaning of the top (5%) frequently used abbreviations in a self-administered questionnaire. Results: More than 900 different abbreviations were identified in the studied sample. Most of them (56%)were used in documenting history and physical examination followed by lab report (20.6%).When medical dictionary was used to identify meaning of the most frequently used abbreviations (top 10%) only (18.4%) of these abbreviations were identified. Meanings of abbreviations were obtained from five general surgery consultants. There were different abbreviations used for a single meaning and different meanings given to a single abbreviation. The factors that significantly affected the number of used abbreviations were length of stay, condition at discharge and department where the patient was staying. The most frequently used abbreviations (top5%) were circulated in a questionnaire to assess the comprehension of these abbreviations among El-demerdash staff. In general, there was poor understanding of the abbreviations used in medical records. Only 3 out of 34 abbreviations were interpreted correctly by more than (50%) of the study sample. Paramedical staff showed lower comprehension level than medical staff. Other factors significantly affected comprehension level of abbreviations include years of experience and last certificate obtained by the participant. Conclusion: The study showed that medical abbreviations are widely used in a non-standardized way in medical records of Eldemerdash hospital. The majority of healthcare professionals had poor understanding of commonly used abbreviations which affects communication during patient care and may lead to medical errors.