Parkinson\'s disease (PD) is a neurodegenerative disorder characterized by the loss of dopaminergic neurons in the substantia nigra. The cerebellum has been implicated in both motor and non-motor symptoms of PD. Although N-glycosylation has been associated with neurodegeneration, altered neuroimmune regulation and synaptic functions in the cerebellum, the structural characteristics of cerebellar N-glycans remain unclear. In this study, N-glycans released from cerebellar lysates of a healthy control and a patient with PD were analyzed by liquid chromatography (LC)-electrospray ionization (ESI)-higher energy collisional dissociation (HCD)-tandem mass spectrometry (MS/MS). Forty-two N-glycans were structurally identical but quantitatively distinct, with PD exhibiting increased sialylation (A2G2S2, A2G2S1, A2G1S1) and decreased mannosylation (M5). Eleven N-glycopeptides were identified by nano LC-MS/MS, including six PD-specific glycopeptides. Three PD-specific N-glycopeptides bearing increased sialylated N-glycans were derived from the plasma fibrinogen γ-chain. Consistently, fibrinogen was detected only in PD by MS/MS-based proteomic analysis. The results indicate that increased sialylation and plasma-derived fibrinogen accumulation may be characteristic features of the PD cerebellum. These aberrant glycosylation patterns may contribute to cerebellar dysfunction and blood–brain barrier disruption, providing insight into potential therapeutic targets for PD.