A method for producing an optically stimulated luminescene (OSL) dosage detection crystal is disclosed, where an Al2O3 is first covered with carbon. The carbon atoms are diffused then in vacuum into the Al2O3 lattices. Then, the oxygen and carbon atoms react with each other in an anneal process under 1 atm. At this time, oxygen and the carbon atoms are enabled to react with each other, and thus C+O result in CO, or C+O2 form CO2, so that oxygen vacancy deficiencies are formed in the Al2O3 crystal. At this time, a uniformly carbon distributed crystal structure is thus simply obtained.