In the condition of the defect of the technology of Landing-Moon, remote sensing is a method to research the evolution, inside structure and surface feature of the Moon, by using remote sensing data and various analysis. Surface roughness is the record of deposit, uplift, erosion and the cover of eruption of volcano on the planetary surface, so the quantitative analysis of roughness could reflect the geological process exactly. The result shows that: 1) the average of RMS height over 1 km-length profile is about 3 m. In addition, within the research scale(0.23 km), the slope of Sinus Iridum area does not exceed 2°.This means that the surface of Sinus Iridum is relatively smooth; 2) the Hurst exponent distributes over a wide-range, 0.40.9, especially in the vertical direction(north-south); 3) in the same scale, Hurst exponent increases from north to south, from west to east, which means the roughness of Sinus Iridum increases from north-west to south-east; 4) the geological age of Sinus Iridum becomes younger from north-west to south-east, which at the same direction of the increase of Hurst exponent; and 5) there is a negative correlation between Hurst exponent and OMAT in the young crater regions.