Parkinson’s disease (PD) is a common neurodegenerative disorder of the central nervous system that severely impairs patients’ motor function and quality of life. Recent studies have demonstrated the promising potential of α-synuclein, immune-inflammatory factors, and biomarkers related to mitochondrial function and oxidative stress for the diagnosis of PD. This review comprehensively summarizes recent progress in laboratory diagnostics and related biomarkers for PD, and discusses novel diagnostic strategies based on the integration of multi-omics, multi-modal biomarkers, and artificial intelligence analysis. Furthermore, it also addresses the key unresolved issues in the field and outlines future directions for biomarker development, with the aim of informing the precise clinical diagnosis, disease monitoring, and treatment evaluation for PD.