Background: The current status of medical malpractice in Tehran medical centers is unclear, while understanding the situation may help the authorities carefully plan, continuously monitor and, consequently, be sensitive to eliminate the weaknesses. Hence, the present study aimed at investigating the existing problems. Methods: In the present Descriptive and cross-sectional study, all patients complaining of the medical staff of public hospitals affiliated to three medical sciences universities (i e, Tehran, Iran, Shahid Beheshti, and Baqiyatallah) were evaluated in terms of demographic characteristics, physicians gender, the type of hospital, the type of specialty, the type of staff, and reason for complaint (disability, death) using a data collection form, and the results were analyzed in SPSS version 18 using the Chi-square and Fisher tests. P-value <0.01 was considered the level of significance. Results: Most of the filed complaints were against hospitals affiliated to Tehran and Shahid Beheshti universities of medical sciences, and 66% against private centers. Most cases won in the court were against general practitioners, dentists, general surgeons, and hospital technicians. The number of malpractices proven for teaching hospitals was significantly lower than that of non-teaching ones. Given the prevalence of plastic surgery in Iranian society, the number of complaints filed from female patients was two-thirds of male ones; almost 50% aged 21-40 years. For some reason, more than three-fourths of wrongful death complaints were for female patients. Conclusion: Complaints of medical malpractice in hospitals are an integral part of physicians and nursing staff work, as the saying goes: an unwritten dictation has no errors.