Introduction:In dentistry, medicine often prescribed to relieve pain and remove infections. Therefore, wrong prescription can lead to a range of problems including lack of pain, antimicrobial treatment failure and the development of resistance to antibiotics.Materials and Methods:In this cross-sectional study, the aim was to evaluate the common errors in written prescriptions by general dentists in Kermanshah in 2014. Dentists received a questionnaire describing five hypothetical patient and the appropriate prescription for the patient in question was asked. Information about age, gender, work experience and the admission in university was collected. The frequency of errors in prescriptions was determined. Data by SPSS 20 statistical software and using statistical t-test, chi-square and Pearson correlation were analyzed (0.05> P).Results:A total of 180 dentists (62.6% male and 37.4% female) with a mean age of 8.23 ± 39.199 participated in this study. Prescription errors include the wrong in pharmaceutical form (11%), not having to write therapeutic dose (13%), writing wrong dose (14%), typos (15%), error prescription (23%) and writing wrong number of drugs (24%). The most frequent errors in the administration of antiviral drugs (31%) and later stages of antifungal drugs (30%), analgesics (23%) and antibiotics (16%) was observed. Males dentists compared with females dentists showed more frequent errors (P=0.046). Error frequency among dentists with a long work history (P>0.001) and the acceptance in the university except for the entrance examination (P=0.041) had a statistically significant relationship.Conclusion:This study showed that the written prescription by general dentists examined contained significant errors and improve prescribing through continuing education of dentists is essential.