The present disclosure provides a surgical navigation system and an instrument guiding method for the same. The instrument guiding method includes: receiving three-dimensional (3D) space information of a predetermined instrument path of an instrument； transmitting the 3D space information to a processing unit such that the processing unit converts the three-dimensional space information to two-dimensional (2D) space information by using a projection model algorithm； and receiving, by at least two image-type projecting units, the 2D space information and projecting at least two patterns into a physical space, wherein the at least two patterns intersect each other to form an intersection area.
