Quercetin is a polyphenolic flavonoid found in many plants and is used as a nutritional supplement. It has been reported to have biological properties that may play an important role in the prevention of human diseases, such as cancer, cardiovascular diseases, diabetes, ulcer, cataract and allergies. In this research, solidified floating organic drop microextraction coupled to high-performance liquid chromatography was used to extract and determine quercetin in Rosa canina L., growing in different areas of Lorestan Province in Iran. The effect of important experimental variables such as type and volume of extracting organic solvent, extraction temperature and time, pH and effect of ionic strength on the extraction recovery was investigated and optimized. Under the optimum extraction conditions, a linear response was obtained over the range of 0.5-40 A mu g mL(-1). Relative standard deviation (RSD%) and enrichment factor were found to be 3.4% and 230, respectively. The proposed method was applied successfully for the determination of quercetin in calycles and fruit of R. canina L. samples. The results showed good agreement compared with those obtained by a validated standard method .