Background: Majority of patients visiting the Dental clinic have poor knowledge about the use of rubber dam, Also Majority of patients have negative attitude towards treated under rubber dam. Objective: To determine the knowledge, attitude and perception of patients towards the use of rubber dam at Riyadh City. Design: Questionnaire survey. Material and Method: Study area: The study will be conducted in Riyadh city, kingdom of Saudi Arabia. Study design the study was a descriptive cross-sectional on Riyadh population. Sample size is of (302) will reached. The study population implicated adult patients aged between 16-50 years of age, This study conducted the time frame of 2 months. Results: A total of 302 questionnaires were distributed, the gender distribution was the 46% patients (n = 163) were male and 54% (n = 139) women. The patients had seen the Rubber Dam before 29.1% (n=88) and 70.9% (n= 214) had never seen the Rubber dam before of the 88 patients who had previous Rubber dam application, had it placed by a dental student 18.9% (n=57) and 6.6% (n=20) by current dentist and 3.6% (n=11) by different dentist. Conclusions: In our study we found the majority of patients have not any knowledge about rubber dam.