The surface elevation of a tilled field shows both oriented and random morphologies. Based on stochastic process theory, the temporal variability of the tilled surface roughness over time fulfills the ergodic property. Characterizing the temporal/spatial variability of the tilled surface by using different indices is beneficial in assessing the tilled quality, studying soil water movement, and for optimal management of agricultural field. Therefore, interpretation of various roughness indices has become a focus in precision agriculture worldwide. In this general review, a broad discussion of soil surface roughness that contains multi-scale models, multi-factor analysis on temporal/spatial variability, and direct or potential utilities in agricultural activity was provided.