The invention discloses a measurement method for determining a position of a crane hook, which comprises the following steps of: 1, during the filling, ensuring that a folding cylinder only takes a working condition, locking a
piston rod of the folding cylinder firmly after extending to the farthest place, finally enabling a folding arm, the folding cylinder and a telescopic arm to form a
rigid body; 2, establishing a sphere coordinate
system with a
hinge point center of the folding arm and a rotary table as a coordinate origin O, wherein the connecting line of the coordinate origin O and thecenter point C of a fixed
pulley of the crane hook is a coordinate
radius phi, and regulating the telescopic direction of the telescopic arm to ensure that the telescopic arm is parallel to the coordinate
radius phi, wherein the state is an initial zero state of an ejector arm of the crane; and 3, during the work, always ensuring that the telescopic direction of the telescopic arm is parallel to the coordinate
radius phi, measuring the length variable value
delta L of the telescopic arm, the length variable value
delta h of a
steel rope, the amplitude angle variable value
delta alpha of the folding arm and the rotary angle theta of the rotary table by using a sensor to obtain the position of the crane hook. The invention reduces the parameters required for determining the position.