Objective: The aim of the study was to evaluate knowledge, attitude and behavior of patients applied to primary health care centers about genetically modified organisms (GMO) in Umraniye.

Material and Method: This descriptive study performed with 294 participants who applied to 11 primary health care centers in one week period and accepted to participate our study in Umraniye. Study data collected by a two part questionnaire which prepared by researchers and had 22 questions, using face to face interview. The data was evaluated by descriptive statatistics, chi square test and logistic regression analysis.

Results: Of 84.0% participants awared of GMO. Of 70.0% participants who awared from GDO heard it from television first and 70.4% of them participants thought GMO harmful for quality of life, 72.9% of them thought they were developed health problems. 85.8% of participants who awared from GMO said they never bought GMO products and 66.8% of them said they never bought GMO products even if they were cheap from others. Being single, not working and thinking of keep abreast of current events were found as decreasing factors on GMO awareness by logistic regression analysis.

Conclusion: Most of the participants were aware of GMO and media found the most important knowledge resource. Approach of participants towards GMO was negative. Especially media had to used effectivelly for raising awareness and knowledge level of community about GMO products.