To provide a rat model with the onset of prostate cancer in which the prostate cancer including an invasive cancer can be developed and can be bred for generations stably. A rat model with the onset of prostate cancer which can develop prostate cancer including invasive cancer and can be bred for generations stably is established by: ligating an SV40 large T antigen gene onto the downstream of rat probasin gene promoter; the resulting PBSVT transgene is introduced into a fertilized egg of a Sprague-Dawley rat; after the introduction, the fertilized egg is transplanted into a recipient rat; a transgenic rat obtained from the recipient rat is then mated with a wild-type Sprague-Dawley rat; the transgenic offspring rats thus obtained are similarly can be bred for generations thereafter; and transgenic rats developing prostate cancer are selected through histopathological observation of the prostate.