In this work, novel visible-light responsive beta-Bi2O3/Ag2WO4 p-n heterojunction photocatalysts were prepared by a simple in situ deposition method and characterized using XRD, FT-IR, SEM, TEM, XPS, UV-vis and PL. The uniform deposition of Ag2WO4 particles on beta-Bi2O3 flakes to form heterojunctions, exhibited excellent photo-catalytic activity for the degradation of methylene blue (MB) under visible light in 30 min. Compared with pure beta-Bi2O3 and Ag2WO4 samples, the kinetic reaction rate constant of MB degradation by beta-Bi2O3/Ag2WO4 was 48.47 times higher than that of beta-Bi2O3, and the degradation rate was as high as 98.8% with good cycling stability.