Abstract: The present invention relates to a method for processing a nuclear fuel comprising a fissile material, SiC and possibly carbon, said method comprising the contacting of said fuel with a chlorine/oxygen mixture at a temperature below 950° C., and more particularly at a temperature between 400 and 900° C., so as to remove the SiC, and the carbon if this is present, from said fuel. The method of the invention makes it possible for example to declad TRISO or BISO nuclear fuel particles, i.e. particles enabling the nuclear fuel to be confined in a sheath or cladding, or to remove an SiC matrix from a fuel having a heterogeneous SiC matrix. The present invention therefore has many applications, especially in the reprocessing of irradiated nuclear fuels.