Provided is a high-strength crystallized glass or substrate having a high visible light transmittance and a good color balance, which is suitable for use in protecting members of portable electronic devices, optical devices and the like. Provided is a crystallized glass comprising, in terms of mol % on an oxide basis: an SiO2 component of 30.0% or more and 70.0% or less, an Al2O3 component of 8.0% or more and 25.0%, an Na2O component of 0% or more and 25.0% or less, an MgO component of 0% or more and 25.0% or less, a ZnO component of 0% or more and 30.0% or less and a TiO2 component of 0% or more and 10.0% or less, the molar ratio [Al2O3/(MgO+ZnO)] having a value of 0.5 or more and 2.0 or less, and comprising one or more selected from RAl2O4, RTi2O5, R2TiO4, R2SiO4, RAl2Si2O8 and R2Al4Si5O18 as a crystal phase.