A system of a plate-type heat exchanger of four liquids of a home boiler using cogeneration is provided to supply the hot water desired by a consumer by using the cogeneration heat source and the heat exchanging plate formed with eight ports and maximizing the hot-water supply and heating performance. A system of a plate-type heat exchanger(10) of four liquids of a home boiler laminated with plural heat exchanging plates(16) by using a first heat source supplied from a cogeneration system comprises a port through which the first heat source is flowed into the heat exchanging plate and discharged; a port through which the fuel and water supplied from the cold water pipe are flowed into the heat exchanging plate and discharged; a port through which the heating water in the boiler is flowed into the heat exchanging plate and discharged; and a port through which the second heat source supplied from the boiler is flowed into the heat exchanging plate and discharged. The fuel and water and the heating water are heat-exchanged with the first heating source.
