Abstract In this article, a method for the estimation of the remaining creep life of steel alloy was studied using the response surface methodology (RSM) based on the central composite design (CCD). Small punch creep tests (SPCT) were performed on the specimens from the aged materials of SA-304L alloy, with different consumed creep life ratios at elevated temperatures. Then, two equations were developed to predict the fracture time and the minimum displacement rate with respect to the consumed creep life ratio of samples, the temperature, and the load of SPCT. The contour plots of responses show that there is a linear relationship between the fracture time and the minimum displacement rate in the logarithmic scale, in accordance with the Monkman-Grant relation.