The invention provides a low density titanium alloy containing aluminum and vitriol and having high strength and casting fluidity, prepared through the following steps of: adding 86.0-90.0wt% of spongy titanium (Ti) basal body into pure aluminum (Al) and an aluminum-vitriol (Al-V) intermediate alloy, weighing 3.32-7.16wt% of pure aluminum and 5.64-8.18wt% of aluminum-vitriol intermediate alloy with the V content of 55 percent, adding into 86.0-90.0wt% of spongy titanium, uniformly stirring to form a Ti-Al-V mixture, pressing the Ti-Al-V mixture through a press machine to prepare a spongy titanium electrode, and then placing the spongy titanium electrode into a vacuum consumable-electrode electric-arc furnace or a vacuum induction furnace for vacuum smelting to obtain the low-density titanium alloy containing 6.85-9.5 percent of Al, 3.1-4.5 percent of vitriol and 86.0-90.0 percent of titanium and having high strength and casting fluidity; the yield of cast golf rod heads reaches 98 percent, and the low-density titanium alloy is suitable for preparing load-bearing parts.