The invention discloses a method for positioning an anchor point of the beam end of a cable stayed bridge and an installation method of a cable guide pipe. The method for positioning the anchor point of the beam end of the cable stayed bridge includes the following steps: constructing a 3D coordinate system, wherein the transverse direction of the cable stayed bridge serves as the X axis, the axial direction of the cable stayed bridge serves as the Y axis, the longitudinal direction of the cable stayed bridge serves as the Z axis, and an original point of the 3D coordinate system serves as a tower central point; according to a known coordinate (X0, Y0 and Z0) of an anchoring central point in the 3D coordinate system and the known included angle alpha between a stayed cable and an XY plane from a design drawing, calculating the space coordinates of four corner points in the installation position of a cable stayed anchor base plate through a reverse-reasoning method. The space coordinates of the four corner points in the installation position of the anchor base plate are firstly calculated, a sample is placed on an anchoring tooth block template, four mounting location points in the marking position are measured, and in the installation process of the anchoring tooth block template, the space locations of the mounting location points and the space locations of the four corner points are adjusted constantly until the space locations of the mounting location points of the anchoring tooth block template coincide with those of the four corner points. The method for positioning the anchor point of the beam end of the cable stayed bridge and the installation method of the cable guide pipe have the advantages of being simple in installation, convenient in construction and the like.