Abstract: The present invention provides a lead-free brass alloy, including 0.3 to 0.8 wt % of aluminum, 0.01 to 0.4 wt % of bismuth, 0.05 to 1.5 wt % of iron and more than 96 wt % of copper and zinc, wherein the copper is present in an amount ranging from 58 to 75 wt %. The brass alloy of the present invention meets the standard of the environmental regulation, wherein the lead content is less than 0.25 wt % based on the weight of the alloy. Further, the brass alloy of the present invention has 0.05 to 1.5 wt % of iron and less than 0.4% of bismuth, so as to lower production cost, eliminate cracks and increase production yield.