Convenient, efficient synthesis methods that improve the emission intensity of rare earth ion doped phosphors are relatively rare. In this study, a simple modified solid-state reaction is proposed. This approach can greatly improve reaction temperature and overcome the requirement for harsh conditions. Its advantages come from the substitution of a solid–solid interface for a solid–gas interface. A novel Ce³⁺ doped SrO phosphor with an enhancive bright cyan emission is prepared and the photoluminescent properties of SrO:Ce³⁺ are first reported. This study will provide valuable clues for synthesizing many other ion doped functional materials besides rare earth ion doped luminescent materials.