Abstract: Method and apparatus for cooling a heated mould (12, 14, 16) of a device (10) for blow-moulding thermoplastic containers, the device including: a mould (12, 14, 16) having an internal face which delimits a moulding cavity (18) and which includes an external face (20, 28) which surrounds the moulding cavity (18); heating elements for heating the mould to a determined temperature and which are deactivated when the cooling method is implemented; characterized in that the mould (12, 14, 16) is cooled by circulating heat-transfer fluid directly in contact with the external face (20, 28) thereof.