A water–gas turbulent lubrication model is established by coupling the generalized Reynolds equation and bubble force equilibrium equation, which includes surface friction force and surface tension of bubbles. The above coupled-equations are solved to obtain load capacity, bubble concentration, and dynamic characteristic for journal bearing. The available experimental results reveal that the load capacity is well predicted by the present model. The theoretical results show that bubble surface tension and low gas volume fraction (β ≤ 0.1) are beneficial in increasing the load capacity of journal bearing, while high gas volume fraction (β ≥ 0.2) have opposite effects. The results also show that water–gas turbulent lubrication can decrease the dynamic characteristic parameters of journal bearing, while increasing the instability whirl frequency of journal bearing.