Abstract: This paper focuses on the mode Ⅱ fracture behaviors of concrete with different coarse aggregate volume fractions by laboratory experiments. Based on the maximum paste thickness (MPT) theory, the empirical relationship between the fracture toughness K_{Ⅱ C} and the coarse aggregate volume fraction V_a was proposed. The mode Ⅱ fracture parameters including peak load, fracture toughness and energy release rate were determined by the compression on half part of the non-notched specimen with different coarse aggregate volume fractions of 19%, 25%, 31% and 37%. The crack distribution on the surface of the fracture ligaments was analyzed. The results show that both mode Ⅱ fracture toughness K_{Ⅱ C} and the critical energy release rate G_{Ⅱ C} enhance with the increase of coarse aggregate volume fraction from 19% to 37% while the crack paths become more tortuous and longer with the increase of coarse aggregate volume fraction. The fracture patterns of all specimens are basically identical, even if the coarse aggregate volume fractions are different. It is found that the shear crack propagation is mainly around the middle ligaments. Additionally, the technique of digital image correlation (DIC) was employed during the tests to track the fracture evolution and characterize the strain localization regions as well as fracture process zone (FPZ). It is also observed by the DIC technique that there are more branches in FPZ and their shapes are more irregular as the coarse aggregate volume fraction increases.