An anode active material for a lithium secondary battery is provided which includes a composite including: a silicon-based material including a lithium silicate; and a lithium-containing phosphate, wherein a peak intensity ratio B/A is 0.01 to 0.5, wherein A is a peak intensity at 2θ = 28.5°, and B is a peak intensity at 2θ = 22.3°, when an X-ray diffraction (XRD) analysis is performed using a Cu-Kα ray.