The present invention relates to an alpha surface pollution- surveying instrument. The characteristic is: its flexible air-pumping pipe is connected with fan, said fan is connected with power supply; one end of air-pumping pipe is positioned on the tested pipe wall; its another end is connected with ionization chamber; the electrode plate of ionization chamber is connected with output end of power supply; the adapter socket on the positive electrode plate of the ionization chamber is connected with input end of I-V converter; the output end of I-V converter is connected with input end of A/D converter; the output end of A/D converter is connected with single-chip computer; said single-chip computer is connected with keyboard, alarm and memory; the power supply is connected with A/D converter.