Numerical control spark machine built-in machining and detection integrated method based on three-dimensional simulation

The invention discloses a method and a system for detecting the internal precision of a numerical control spark machine. The method comprises the following steps: arranging a detection point position needing to be measured in a three-dimensional digital model through computer-aided manufacturing software; extracting coordinate information of a ball mark corresponding to each detection point location under the reference of the simulation reference coordinate system; converting the extracted coordinate information into a variable format which can be identified by a machine tool measurement program, and inputting into a measurement program file; the electrode is fed to the to-be-machined workpiece to complete machining; calling a measurement program file to perform online measurement on each detection point; manual error judgment is carried out according to the output measurement precision; the numerical control spark machine internal machining detection device has the advantages that machining and detection in