Natural weathering processes can make coal surface more hydrophilic since the increase of content of hydrophilic functional groups (C-O, C=O and COOH) and the decrease of content of hydrophobic functional groups (C-C and C-H) on coal surface, and hence the flotation recovery of fine coal is reduced. In this paper, bituminous coal was used as coal samples and XPS was used to indicate the changes in surface properties of bituminous coal before and after natural weathering processes. A series of flotation tests were conducted in order to investigate the changes in the flotation kinetic of bituminous coal before and after natural weathering processes. Throughout this paper, the flotation kinetic was found to be changed. The classical first-order rate constant (k) of bituminous coal flotation was reduced after natural weathering processes. The relationship between the classical first-order rate constant (k) and the hydrophilicity ability (HA) was given.