alpha-Synuclein is a major component of Lewy bodies in the brains of patients with Parkinson's disease (PD) as well as of neuronal/glial inclusions in a subset of neurodegenerative disorders collectively termed synucleinopathies. Here we studied by immunohistochemistry the accumulation of alpha-synuclein in transgenic (TG) Drosophila overexpressing wild-type (WT) or familial PD-linked mutant (i.e. A30P and A53T) alpha-synuclein in neurons, with special reference to the phosphorylation at Ser129, that is characteristic of human synucleinopathy lesions. Progressive accumulation of human alpha-synuclein was widely observed in the cell bodies and neurites of major neuronal nuclei in TG Drosophila brains, and phosphorylation of alpha-synuclein at Ser129 was detected in a limited subset of neurons approximately 1 week after alpha-synuclein immunoreactivity was first detected. Phosphorylated alpha-synuclein was most abundant in A53T mutant, followed by A30P and WT Drosophila. These results suggest that accumulation and phosphorylation of alpha-synuclein is recapitulated in neurons of alpha-synuclein transgenic Drosophila, that underscores the relevance of this model to human synucleinopatheis.