Protecting and improving the structural properties of soil constitutes the basis for the efficient and sustainable utilization. The purpose of this research was to determine the effects of biochar application with different rates on aggregate stability (AS) and modulus of rupture (MR) of a poorly structured soil under laboratory conditions. During the experiment, 0 (control), 5, 10, 20, and 40 g/kg biochar rates were applied to soil and then incubated for 30 days. According to the results, biochar applications significantly affected both modulus of rupture and aggregate stability values of the soil. However 5, 10, 20 and 40 g/kg rates of biochar decreased soil modulus of rupture by 9%, 26%, 42% and 61% respectively, increased aggregate stability values by 3%, 27%, 178% and 189% respectively compared with the control. According to finding obtained from the research, biochar which is known as a soil amendment was determined to be a promising agricultural practice for improving soil structure in the short period of time.