To provide a component mounting system which can be used for other mounting machines without modifying its program.

This system is provided with plural component supply means 22 where supply position numbers are set; a mounting instrument 26 which receives components to be attached onto the component supply means 22 and mounts them on a member to be mounted 25; a 1st input means 30 which predetermines component identification numbers corresponding to component kinds and inputs pairs of supply position numbers and identification numbers of components mounted at the positions; a 1st storage means 32 which stores their information; a 2nd input means 31 which inputs component identification numbers, mount positions, etc.; a 2nd storage means 33 which stores their information; and a 1st mounting control means 28 which allows an extracting means 29 to extract a supply position number corresponding to a component identification number from the 1st storage means 32 according to the order of mounting stored in the 2nd storage means 33, and controls the mounting instrument 26 so as to mount a component attached onto the component supply means 22 corresponding to the result.