In a method for determining ricochet vectors of a probe of a coordinate measuring machine (CMM) using a computing device, the computing device sets an approach distance between the probe and a manufactured object. Coordinates of a center of the probe and an initial vector of the probe for each measurement point of the manufactured object are obtained when the probe is manually operated to measure the manufactured object. A measurement element of the manufactured object is fit according to all measurement points of the manufactured object. For each measurement point, an approach point of the manufactured object is calculated, a position relation between the approach point and the measurement element of the manufactured object is determined, and a ricochet vector of the probe is calculated according to the position relation.