Improvement for the adhesive property of the DLC (diamond-like carbon) film on the protected substrate has obvious value in the actual application, and the reason for the validity of the Cu-based multi-layer DLC film designed in our former research was analyzed in the view of the micro-theory. Then, in order to optimize the structure of the multi-layer film and improve its performance in the practical application, the influences of the thickness ratio between the DLC layer and SiC layer in the periodic layer on the adhesion property, nano-hardness and wear property were studied. The results of the nano-scratch and nano-indentation tests show that the adhesive property and nano-hardness of the Cu-based multi-layer DLC film decreased and its nano-hardness increased, respectively, while the thickness ratio was maintained in the increasing state. Critical load of the multi-layer DLC film on the Cu substrate could approach that of the single-layer DLC film with the thickness of 400 nm on the Si substrate, when the thickness ratio was below 2.3. Meanwhile, the wear property of the Cu-based multi-layer DLC film was approximately close to that of the pure DLC film.