The invention discloses an ordinary clean cement paste of early age temperature conductivity coefficient prediction method based on a multi-scale model. The ordinary clean cement paste early-age temperature conductivity coefficient prediction method based on the multi-scale model includes that heterogeneous and multi-scale division is conducted according to a micro-structure and composition of ordinary clean cement paste in an early age, a typical phase is contained at each scale, volume percentages of different ages and phases are calculated, and temperature conductivity coefficients of the clean cement paste in the early age are calculated and obtained through a generalized self-consistent method according to parameters of volume percentage of each phase, temperature conductivity coefficients and the like at each scale. Influences of clean cement paste early-age micro-structure formation and evolution, and performance of component materials on clean cement paste macroscopic temperature conductivity coefficients are considered, influence factors considered are comprehensive and reasonable, and the ordinary clean cement paste early-age temperature conductivity coefficient prediction method based on the multi-scale model is simple in form and convenient to use. The temperature conductivity coefficients of the clean cement paste in the early age with different water-cement ratios, different kinds of cement, and different curing temperatures can be predicted more correctly according to a prediction model built with the ordinary clean cement paste early-age temperature conductivity coefficient prediction method based on the multi-scale model.