Classical swine fever virus (CSFV) is the causative agent of classical swine fever (CSF), a highly contagious and economically important disease of pigs. The envelope glycoprotein E2 of CSFV is the major antigen that induces neutralizing antibodies and confers protection against CSFV infections. Previously, we developed a murine monoclonal antibody (MAb), HQ06, against the E2 protein of CSFV. To produce the antibody conveniently and stably, the genes coding for the variable regions of the heavy and light chains of HQ06 and constant region genes from the swine antibody were fused and cloned into lentiviral expression vectors to express a recombinant porcinized MAb (rHQ06(Sw)) in mammalian cells. rHQ06(Sw) was able to react with the E2 protein or the CSFV virions specifically in different assays. Notably, rHQ06(Sw) could neutralize CSFV infection in a dose-dependent manner. Taken together, the functional porcinized MAb rHQ06(Sw) was generated, which can be used to develop novel diagnostic assays or to investigate the structure and functions of the E2 protein.