The present invention relates to a composite, a preparation method of said composite and a catalyst using said composite. Said composite basically consists of laminated clay uniformly dispersed in the inorganic oxide matrix. The clay is dispersed in the form of that the clay layer is fully enveloped by inorganic oxide matrix. The inorganic oxide includes aluminium oxide, titanium dioxide, silicon dioxide, zirconium dioxide, phosphorus pentoxide and their mixture. The clay may be natural clay, such as montmorillonoid, metal ion exchanged (Fe+3 ion exchanged) clay or support-type clay, such as hydrated aluminium chloride (ACH) supporttype clay. Said composite can be used as the catalyst for alkylate reaction or hydrocracking reaction or an effective catalyst formed from the metal dispersed on said composite for hydrocracking reaction or alkylate reaction.