M icrocracking and bridging are major mechanisms in the fracture of quasi-brittle materials such as concrete, rock, and ceramics. In the present paper, an analytical model of the fracture process zone which includes both microcracking and bridging is presented to estimate the effects of microcracking and bridging. The bridging zone is represented by a Dugdale-Barenblatt-type model in which the bridging stress and the opening displacement satisfy the tension-softening curve which is the inelastic component of the post-peak behavior in a uniaxial tension test. The microcracking zone is modeled as a region with distributed microcracks. A simple microcracking law is introduced and the microcrack density is determined as a function of the maximum tensile stress based on the pre-peak stress-strain curve in a uniaxial tension test. With given material properties on bridging and microcracking, the model predicts the shape and size of the microcracking zone, the distribution of microcrack density and the value of the applied stress intensity factor for a given length of the bridging zone. Results with effects of both microcracking and bridging are compared with those with only bridging. The introduction of microcracking results in a relative increase in the toughness and the relative size of the microcracking zone. Absolute values of the toughness and the size of the microcracking zone are determined from material parameters on bridging. Among the microcracking parameters, the critical microcracking density, which is the ratio of the inelastic strain to the elastic strain at the tensile strength, is found to be the governing parameter. It is shown that the toughness due to microcracking varies for different materials, but it remains a small portion of the total toughness for existing quasi-brittle materials.