The invention relates to a system and method for testing pressing force of a high pressure connector. The system comprises a high pressure connector, a compression nut, a fuel injector, at least one strain foil and a strain recorder; the high pressure connector is connected with the fuel injector through the compression nut; the strain foil is attached to the high pressure connector and is used for measuring the strain of the high pressure connector; the strain recorder is connected with the strain foil and is used for obtaining the pressing force of the high pressure connector to the fuel injector according to the strain measured by the strain foil. According to the system and method for testing pressing force of a high pressure connector, by means of the strain foil attached to the high pressure connector, the strain for tightly screwing the compression nut is measured by the strain foil, the pressing force of the high pressure connector to the fuel injector is accurately obtained by the strain recorder according to the strain, and therefore the assembly technology of the fuel injector and the high pressure connector is optimized.