An in situ Raman spectroscopic study was conducted to explore the pressure-induced phase transformation of ferrite MgFe2O4 to 51.6 GPa. Results indicate that MgFe2O4 transforms to a high pressure polymorphism at a pressure of 27.7 GPa, which was assigned to an orthorhombic structure. Upon release of pressure to ambient conditions, this high pressure polymorphism of MgFe2O4 remains stable. The crystallization of high pressure phase of MgFe2O4 is dominated by a diffusionless crystallizing mechanism. (C) 2002 Elsevier Science Ltd. All rights reserved.