A support frame of a CT imaging system, comprising: a connection flat plate portion ; a support body portion disposed on the connection flat plate portion ; an X-ray source installation reference portion disposed on the connection flat plate portion ; an electrical installation portion ; a cooling component installation portion ; and a through hole , wherein the through hole is surrounded by the support body portion , the X-ray source installation reference portion , the electrical installation portion and the cooling component installation portion , and the through hole penetrates the connection flat plate portion , characterized in that two ends of the support body portion are connected to the electrical installation portion and the cooling component installation portion respectively, the X-ray source installation reference portion is opposite to the support body portion , and the X-ray source installation reference portion is located between the electrical installation portion and the cooling component installation portion , a circumferential surface of the support body portion is provided with an integrally formed detector installation portion , and the detector installation portion has a strip shape, the connection flat plate portion , the support body portion , the X-ray source installation reference portion , the electrical installation portion , the cooling component installation portion and the detector installation portion are an integrally cast part, and an end portion of the support body portion opposite to the connection flat plate portion is provided with at least one heat dissipation groove . a connection flat plate portion ; a support body portion disposed on the connection flat plate portion ; an X-ray source installation reference portion disposed on the connection flat plate portion ; an electrical installation portion ; a cooling component installation portion ; and a through hole , wherein the through hole is surrounded by the support body portion , the X-ray source installation reference portion , the electrical installation portion and the cooling component installation portion , and the through hole penetrates the connection flat plate portion , characterized in that two ends of the support body portion are connected to the electrical installation portion and the cooling component installation portion respectively, the X-ray source installation reference portion is opposite to the support body portion , and the X-ray source installation reference portion is located between the electrical installation portion and the cooling component installation portion , a circumferential surface of the support body portion is provided with an integrally formed detector installation portion , and the detector installation portion has a strip shape, the connection flat plate portion , the support body portion , the X-ray source installation reference portion , the electrical installation portion , the cooling component installation portion and the detector installation portion are an integrally cast part, and an end portion of the support body portion opposite to the connection flat plate portion is provided with at least one heat dissipation groove . <EOS>