The invention discloses an energy-saving type offset printing unit, an energy-saving type printing machine and an energy-saving type printing system, which belong to a printing machine of the technical field of printing equipment. The invention aims at providing the energy-saving type offset printing unit with high heat exchange efficiency, the energy-saving type printing machine adopting the energy-saving type offset printing unit and the energy-saving type printing system adopting the energy-saving type printing machine, so that the drying effect of a printed material is improved. The offset printing unit comprises four color groups, wherein every two adjacent color groups are connected with each other by a paper transmission drum; a rotating block is arranged at each of the two ends in the axial direction of each of the paper transmission drums; the two ends of each of the paper transmission drums are connected with an air inlet pipe and an air outlet pipe by the rotating blocks; each of the paper transmission drums comprises an inner-layer drum body and an outer-layer drum body; a partition plate is arranged in each of the inner-layer drum bodies and is used for dividing an inner cavity of the inner-layer drum body into flow channels; one end of each of the flow channels is communicated with an air inlet formed on each of the inner-layer drum bodies, and the other end of each of the flow channels is communicated with an air outlet formed on each of the inner-layer drum bodies; the flowing direction of air in the flow channels is opposite to the rotating direction of the outer-layer drum bodies.