Lewy bodies (LBs) in dopaminergic neurons in substantia nigra pars compacta (SNpc) are the cardinal pathological hallmark of Parkinson's disease (PD), while LBs and/ or Lewy neurites are also seen in non-dopaminergic neurons in other brain regions of patients with PD, such as noradrenergic neurons in locus coeruleus (LC), and cholinergic neurons in prefrontal cortex (PFC) and temporal cortex (TC). To explicit protein contents of LBs in PD, here is an article that demonstrates five aspects of protein constitution of LBs by analyzing protein bioinformatics datasets related to LBs in PD: (1) LBs is filled with 2 types of alpha-synuclein (α-SYN) positive fibrilar aggregates and/or 6 types of α-SYN positive non-fibrilar aggregates (described frequently in literature as oligomers); (2) modification forms of pathological α-SYN in LBs are often associated with 5 species of chemical modifiers; (3) 19 α-SYN-associated proteins rich in LBs are respectively colocalized with α-SYN; (4) 117 previously reported proteins in LBs in immunochemistry study are at least classified into 10 different groups of functional proteins with close relationship; (5) proteomics database as protein candidate resource for LBs contains 84, 124 and 120 proteins identified respectively from raw tissue samples of LC, SNpc and PFC regions, and 108 proteins identified from a cellular separation of analyte captured from TC region, and 29 proteins identified from a sub-cellular fraction of analyte isolated from TC region. It is suggested that the aforementioned aspects comprehensively and fundamentally reflect protein composition of LBs in PD.