The chemical composition and surface structure of glass affect its wettability and can thus lead to the formation of various functional surfaces. This study examined the influence of the structural changes induced by the heat treatment of sodium borosilicate glass on its wettability. Specifically, 15Na2O‐40B2O3‐45SiO2 glass was prepared through melt‐quenching. The obtained glass was subjected to heat treatment at 600°C for 3 h. The heat‐treated glass exhibited a higher hydrophilicity and surface free energy than the nontreated glass. The heat treatment led to a variation in the relative ratio associated with the boron coordination number and nonbridging oxygen. Therefore, the heat‐treatment‐induced changes in the glass structure considerably enhanced the wettability of the glass.