Compressive strength and uniaxial tensile tests were conducted on polyethylene fiber reinforced engineered cementitious composites (PE-ECC) with varying steel slag powder content (0%, 20%, 40% and 60%, mass fraction) to examine the influence of steel slag powder on the compressive strength of PE-ECC and the change rule of tensile stress-strain. Microstructural analysis of the interface between PE fiber and steel slag powder-incorporated engineered cementitious composites (ECC) matrix was performed using scanning electron microscopy (SEM). The results show that the incorporation of steel slag powder reduces the compressive strength, cracking stress and peak stress under tension of PE-ECC, while improving the tensile toughness. Additionally, the presence of steel slag powder enhances the bonding state between fiber and matrix. The tensile stress-strain relationship of PE-ECC can be effectively described using bilinear constitutive model. The findings of this study provide valuable insights for diversified preparation and engineering applications of ECC.