In a magnetic disc cartridge, a magnetic disc is contained for rotation in a casing which is provided with a magnetic head insertion opening and a shutter member for opening and closing the magnetic head insertion opening. The shutter member is urged by a shutter spring to a closing position in which it closes the magnetic head insertion opening. The shutter spring is formed of a coiled metal spring which is engaged with the casing at one end and with the shutter member at the other end and urges the shutter member to the closing position under its resiliency generated by deflection thereof.