To provide a method for producing chemically tempered glass, whereby frequency of replacement of the molten salt can be reduced. A method for producing chemically tempered glass, which comprises repeating ion exchange treatment of immersing glass in a molten salt, wherein the glass comprises, as represented by mole percentage, from 61 to 77% of SiO2, from 1 to 18% of Al2O3, from 3 to 15% of MgO, from 0 to 5% of CaO, from 0 to 4% of ZrO2, from 8 to 18% of Na2O and from 0 to 6% of K2O; SiO2+Al2O3 is from 65 to 85%; MgO+CaO is from 3 to 15%; and R calculated by the following formula by using contents of the respective components, is at least 0.66:
R=0.029×SiO2+0.021×Al2O3+0.016×MgO−0.004×CaO+0.016×ZrO2+0.029×Na2O+0×K2O−2.002