Heterojunction with nano-level interfacial contact has an advantage in improving the transfer capacity of photongenerated carriers. In consequence, a heterojunction composite with nano-level interfacial contact was developed by establishing CdSe/Al2TiO5 heterojunction composites. The heterojunction composite was established by combining Al2TiO5 and CdSe nanocrystals. They provided superior nano-level interfacial contact. The photocatalytic activity of heterojunction composites were illustrated to be significantly improved compared to that of pure Al2TiO5 and CdSe nanocrystals. Moreover, the photocurrent intensity of heterojunction composites displays a several times enhancement, implying the promotion of photocatalytic activity was owned to the nano-level interfacial contact with ideal photogenerated electron-hole pairs transfer behavior.