In this paper, aqueous extract fractions from byproducts of the processing of canned bamboo shoots, including boiled water, filled liquid, and squeezed juice, were obtained by 5 kDa molecular cutoff membranes and marcoporous resin DA201-C treatment. The enriched bamboo shoot angiotensin converting enzyme (ACE) inhibitory peptide preparation fraction (called BSP for short) was extracted with ethyl acetate and n-butanol. The ethyl acetate fraction and n-butanol fraction exhibited higher antioxidant capacities than the leaving water fraction (BSML), which was attributed to the higher phenolic acid and flavonoid content of both fractions, while BSML exhibited the strongest ACE inhibitory activity. Sephadex G-15 gel filtration and semipreparative high-performance liquid chromatography were used for further purification of bamboo shoot ACE inhibitory peptide from BSML. Asp-Tyr was identified as the key active component by ultra-high-performance liquid chromatography and electrospray ionization tandem mass spectrometry. A short-term antihypertensive assay stated that both Asp-Tyr [10 mg day(-1) (kg of body weight)(-1)] and BSP [50 mg day(-1) (kg of body weight)(-1)] could significantly reduce the systolic blood pressure of spontaneously hypertensive rats (3-6 h). This study provides further examples of utilization of byproducts from the processing of canned bamboo shoots for the prevention of hypertension and attenuation of oxidative stress.