Unit for secure processing access controlled audio/video data capable of receiving control messages (ECM) comprising at least one first control word (CW1) and first right execution parameters (C1), at least one second control word (CW2) and second right execution parameters (C2), said processing unit being connected to a first access control device (CA1), said processing unit is characterized in that it comprises: —means for verifying and applying the first right execution parameters (C1) in relation to the contents of a memory (M1) of said first access control device (CA1) and means for obtaining the first control word CW1, —a second access control device (CA2) integrated into the processing unit UT including means for verifying and applying the second right execution parameters (C2) in relation to the contents of a memory (M2) associated to said second access control device (CA2) and means for obtaining the second control word (CW2), —a deciphering module (MD) capable of deciphering, sequentially with the first and the second control word (CW1) and (CW2), the access controlled audio/video data, said control words (CW1) and (CW2) being provided by the first and second access control devices (CA1, CA2) and stored in said deciphering module (MD). A method for secure processing digital access controlled audio/video data carried out by said unit is also an object of the present invention.