The invention discloses a full-plastic heat exchanger. The full-plastic heat exchanger comprises an upper chamber and a lower chamber, each of the upper chamber and the lower chamber is provided with an interior storage cavity, a medium inlet convenient for entering of a heating or refrigerating liquid medium is formed in the upper chamber, and a medium outlet allowing the liquid medium to flow out after working is formed in the lower chamber. The full-plastic heat exchanger is characterized in that the upper chamber and the lower chamber are communicated with each other via a plurality of uniformly distributed heat exchange pipes, and the liquid medium flows along the heat exchange pipes to achieve heat exchanging. Compared with an existing metal heat exchanger, the full-plastic heat exchanger has the advantages the components such as the upper chamber, the lower chamber and the heat exchange pipes are made of plastic, so that scale formation prevention, no formation of heavy metal ions, corrosion resistance and no pollution to water are achieved; the full-plastic heat exchanger also has the advantages of low energy consumption in a production process, low in environment pollution and production cost, remarkable beneficial effect and convenience in application and promotion.