The aim of this study was to investigate the role of retained acupuncture (RA) in neurotoxin-induced Parkinson's disease (PD) mice. Male C57BL/6 mice were injected with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) to induce the PD model. The mice were divided into four groups, namely, (1) normal; (2) MPTP+retained acupuncture (RA); (3) MPTP+electroacupuncture (EA); (4) MPTP+sham acupuncture (SA). After mice being manipulated with/without acupuncture at acupoints (Daling, PC 7), groups 2-4 were injected with MPTP (15 mg/kg/d). The mice were evaluated for behavioral changes, in terms of time of landing, after acupuncture treatment. The animals were sacrificed and their brains assayed for dopamine and its metabolites and tyrosine hydroxylase (TH) expression by using HPLC and immunohistochemistry/Western blotting, respectively. [(123)I] IBZM-SPECT imaging between SA and RA groups were compared. The results showed that the time of landing of the three groups with treatment was significant longer than group 1 (normal) (4.33±0.15 s). Nonetheless, group 2 (RA) (7.13±0.20 s) had a shorter time of landing than group 4 (SA) (7.89±0.46 s). The number of TH (+) neurons and the expression of TH proteins were significantly higher in the RA group than in the SA/EA groups. RA also increased the uptake of [(123)I] IBZM into the triatum compared to the SA group. We conclude that RA possibly attenuates neuronal damage in MPTP-induced PD mice, which suggests RA may be useful as a complementary strategy when treating human PD.