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Background Biallelic PLA2G6 mutations are associated with early onset autosomal recessive parkinsonism, exhibiting a broad spectrum of clinical heterogeneity.Objective To comprehensively characterise the clinical, imaging and genetic features of PLA2G6-related parkinsonism.Methods We report 14 new cases of PLA2G6-related parkinsonism in Southwest China and conduct a systematic literature review.Results Among the 14 patients in our cohort, 16 PLA2G6 variants were identified, including seven novel and nine previously reported variants. The mean age at symptom onset was 26.50±6.57 years. The most common initial presentation was parkinsonism (9/14, 64.3%), followed by gait disturbance (6/14, 42.9%) and psychiatric symptoms (1/14, 7.1%). A literature review identified 118 patients with PLA2G6-related parkinsonism, with a mean age at onset of 24.53±8.84 years. The most common initial clinical features included parkinsonism (61/117, 52.1%), cerebellar signs (46/85, 54.1%), cognitive impairment (65/92, 70.7%) and psychiatric symptoms (80/93, 86.0%). Subgroup analysis showed that the mean age at symptom onset was older in Chinese patients (26.65±7.08 years) compared with those of European ancestry (20.83±9.79 years) (p=0.016). Additionally, patients of European ancestry showed delayed parkinsonism 5.35±8.14 years after onset. Iron deposition was reported more frequently in patients of European ancestry (10/16, 62.5%) than that in Chinese patients (6/37, 16.2%) (p=0.0002).Conclusion Our study provides new insights on the diverse clinical spectrum of PLA2G6-related parkinsonism, encompassing parkinsonian features, psychiatric symptoms, cognitive impairment and early levodopa-induced motor complications.