An attempt on a simple grain refinement technique is practiced on the annealed pure iron bars with torsion processes and heat treatments. Two types of torsion process, i.e., torsion to rupture and torsion interrupt processes, are conducted on the specimen bars. Heat treatments on the torsion processed specimens are then performed at 500°C, 550°C and 600°C for 1h, 3h and 8h, respectively. Microstructures and mechanical properties of the specimens are investigated. As a result, the fine-grained microstructures, particularly with an average grain diameter of about 1/48 of the as-annealed material, are obtained. It is confirmed that the grain refinement behavior is closely related with the torsion deformations as well as the recrystallization conditions. And, under some conditions of torsion and recrystallization processes, mechanical properties of the specimens are improved by the grain refinement.