Parkinson's disease (PD) is one of the most common forms of neurodegenerative diseases, inflicting motor system deficits in over 6.2 million individuals globally. Ginkgolide B (GB), an active terpene lactone derived from Ginkgo biloba, has been shown to possess neuroprotective activities, which make it ideally suited for the treatment of PD. However, GB is largely insoluble in water and as a consequence it has poor bioavailability when administered orally, thus precluding sufficient blood and brain exposure and hindering its anti-Parkinsonian efficacy and clinical application. The present study sought to utilize nanoparticles in order to encapsulate and mediate the sustained release of GB in the bloodstream, thereby facilitating better brain accumulation and PD treatment. We prepared nanoparticles (particle size: 91.26 ± 1.34 nm) containing GB (GB-NPs) via encapsulating this compound within poly (ethylene glycol)-co-poly (ε-caprolactone) (PEG-PCL) nanoparticles with an 87.52% encapsulation efficiency and a 26.93% drug loading efficiency. The obtained GB-NPs exhibited an initial rapid release of ~30% within the first 2 h in vitro, with ~94% release by 48 h. As compared with raw GB, GB-NPs afforded markedly increased cellular uptake and permeability in MDCK cells (p<0.01). In addition, GB-NPs showed a significant neuroprotective effect against 1-methyl-4-phenylpyridinium ion (MPP+)-induced damage in SH-SY5Y cells. There was no apparent toxicity upon administration to zebrafish, with unaltered hatching rate, survival rate, heart rate, body length, or overall morphology. These GB-NPs were further orally administered to rats, leading to rapid drug absorption with maximal plasma concentrations of 3.86 ± 0.33 μg/ml after 4.50 ± 0.55 h. Relative to non-encapsulated GB, the Cmax and AUC0-48 h of GB-NPs were increased nearly 11.03- and 13.94-fold, respectively. GB-NPs also resulted in dramatically higher brain Cmax and AUC0-28 h values of 0.17 ± 0.01 μg/g and 5.10 ± 0.49 μg.h/g, respectively in comparison with the unformulated GB. In a murine model of PD, GB-NPs showed much better therapeutic efficacy and lower systemic toxicity than free GB after oral administration. In summary, these results provide evidence that sustained-released PEG-PCL nanoparticles are able to achieve effective oral bioavailability, brain accumulation and bioactivity for the Biopharmaceutics Classification System (BCS) Class II compound, GB.