To discover the anti-oxidative phytochemicals from the leaves of Phyllostachys nigra and evaluate the activity of these compounds for the treatment of Alzheimer's disease, phytochemical studies have led to the identification of 15 compounds including orientin (1), isoorientin (2), vitexin (3), isovitexin (4), tricin (5), tricin-7-O-beta-D-glucopyranoside (6), luteolin (7), luteolin-7-O-beta-D-glucopyranoside (8), p-hydroxy-cinnamic acid (9), caffeic acid (10), ferulic acid (11), chlorogenic acid (12), vanillic acid (13), beta-sitosterol (14) and daucosterol (15). Then, their anti-oxidative and neuroprotective activities in vitro were carried out. The results showed the anti-oxidative constituents can ameliorate the NG108-15 cells injury induced by H2O2 through proliferating NG108-15 cells, reducing the production of malondialdehyde, decreasing the activity of lactate dehydrogenase, increasing the activity of superoxide dismutase, maintaining the mitochondrial membrane potential and blocking the activation of caspase-3, which confirms the mechanism for the neuroprotective activity of these natural compounds is the response to oxidative stress.