Whether the relationship between type 2 diabetes mellitus (T2DM) and osteoarthritis (OA) could solely be attributed to the shared risk facts, like obesity, remains controversial. There have been a large number of studies that revealed the critical role of abnormal glycosylation in the pathogenesis of OA, as well as in T2DM. Therefore, we speculated that T2DM could probably contribute to the pathogenesis of OA through intrinsic mechanisms about N-glycosylation aberrations. With the N-glycoproteomics techniques, we compared the alteration of N-glycosylated protein abundance in cartilage samples from OA patients and OA complicated with T2DM (DM-OA) patients, as well as from traumatic joint injury patients (NC) as control. We identified a total of 847 N-glycosylation sites corresponding to 729 N-glycosylated peptides fragments from 374 N-glycosylated proteins. The numbers of N-glycosylated proteins in DM-OA group tended to decrease compared to OA and NC groups. We identified a total of 22 upregulated and 1 down-regulated N-glycosylated peptides in OA group compared to NC group, while only three of them, including fibronectin (FN1) at position N1007, cartilage intermediate layer protein 1 (CILP) at N346, and collagen type VI alpha 1 chain (COL6A1) at N804, were also identified in DM-OA group. Compared to OA group, the down-regulation of SPARC (N116), COL6A2 (N785), and aspirin (N282), as well as upregulation of complement C8A (N437), were the most remarkable alterations in DM-OA group. The differential expressed N-glycosylated proteins between OA and DM-OA groups were mainly located extracellularly, and enriched in the KEGG pathways involving PI3K/Akt signaling, focal adhesion, and ECM-receptor interaction. Their predicted protein-protein interactions were also depicted. We showed the general characteristic of N-glycosylation aberrations in OA and DM-OA. Moreover, considering the deteriorative role of the PI3K/Akt pathway in OA, the decreased N-glycosylated proteins involved in PI3K/Akt pathway in DM-OA group might probably alleviate the Akt-related metabolic-inflammation. On the contrary, the upregulated glycosylated complement C8 in DM-OA group might probably augment the activity of membrane attack complex (MAC) and thereby exacerbate the cartilage destruction. Although further confirmation was in need, our hypothesis proposed a possible explanation for the controversy about the relationship between OA and T2DM.