Abstract: Objective To detect the expression level of microRNA-214 (miR-214) in cartilage and subchondral bone of different graded osteoarthritis (OA), which was classified by X-ray diagnosis criteria of Kellgren and Lawrence, and provide theoretical foundation for researching the role of miR-214 in OA development. Methods Tibial plateaus of OA patients were collected from those who underwent total knee arthroplasty (TKA) and amputation. Forty samples were divided into 4 groups by K-L osteoarthritis scoring system: gradeⅠgroup (n=10), gradeⅡgroup (n=10), gradeⅢgroup (n=10), and gradeⅣgroup (n=10). After getting the samples, we segregated cartilage and subchondral bone, and the expression level of miR-214 by real-time PCR was tested. Results miR-214 was examined in all cartilage and subchondral bone. The expression level of miR-214 was compared in four groups, and it showed a rising trend with significant difference (P< 0.05). Positive correlation was found between the severity of OA and the expression level of miR-214. Among the four groups, the level of miR-214 in subchondral bone was highest. Conclusion The expression level of miR-214 in 4 groups is keeping rising, which is related to the severity of OA progression. And the expression level of miR-214 also has obvious change in subchondral bone. Our findings indicate that miR-214 has intertwined relationship with the development and progression of OA, which provides theoretical foundation for OA development and treatment.