Polypropylene fiber reinforced engineered cementitious composite (PP-ECC) is a ductile material with good properties, low cost and wide application prospect. In this study, the impact of varying fiber content on the tensile mechanical behavior of PP-ECC was explored, encompassing parameters such as initial cracking stress and strain, peak stress and strain, stress-strain relationship, and elastic modulus. Drawing from uniaxial tensile tests, damage factors were defined and a constitutive model tailored to the tensile characteristics of PP-ECC was formulated, leveraging existing engineered cementitious composite (ECC) damage constitutive models and theories. Refinements were made to the fitting function of damage factor, employing a univariate 6th-degree function and utilizing Origin and Matlab for parameter calculation and identification within the damage factor function. The optimized constitutive model demonstrates enhance alignment with experimental results, marking a significant improvement in model accuracy.