This research aims to evaluate the lightweight burnt clay brick aggregate concrete factor (λ) which is commonly used as coarse aggregate in Bangladesh as well as Asia regions. The pull-out tests were carried out on four different types of concrete cylinder specimens (100 mm by 200 mm) made with natural crushed stone and first class burnt clay brick aggregates to determine the aggregate concrete factor (λ) and bond strength. Three different rebar diameter of 8 mm, 10 mm, and 12 mm with two different embedded lengths of 100 mm and 200 mm were investigated. In addition, compressive and splitting tensile strength tests were also performed to calculate bond strength and then λ. The experimental results showed that bond strength of 10 mm diameter rebar is higher compared to other bar diameter for both aggregates and both embedded length of 100 and 200 mm. While the bond strength of 200 mm embedded length rebar is higher than the embedded length of 100 mm. From this research study, it has been found that the average λ equal to 0.88 for Bangladeshi burnt clay brick aggregate. However, based on the test results a new equation is proposed for the lightweight brick aggregate concrete factor (λ).