PURPOSE: To evaluate the surface physical properties of an article to be evaluated without receiving the effect of thermal expansion.

CONSTITUTION: In a surface physical property evaluation device, the relation between the load applied to a penetrator 10 by a load means 1 and the displacement quantity of the penetrator 10 measured by a displacement quantity measuring means 4 is calculated by an operation means 14. At this time, the operation means 14 calculates a time change rate showing 'displacement quantity/hr of penetrator due to thermal expansion' from the displacement quantity due to thermal expansion of the penetrator measured when the penetrator 10 is brought into contact with the surface of an article to be evaluated. The displacement of thermal expansion contained in the displacement quantity measured when the penetrator 10 is pushed in is estimated from the time change rate and removed from the displacement quantity measured when the penetrator is pushed in to calculate the real displacement quantity of the penetrator 10.