An external heat dissipation device includes an airflow-guiding base and a refrigerating device. The airflow-guiding base has a supporting surface and a perforation located thereon. The refrigerating device includes a casing, a thermoelectric cooler, a cold air transferring assembly and a hot air transferring assembly. The casing has a storage space. The thermoelectric cooler is located in the storage space and has a cooling surface and a heat releasing surface opposite to each other. The cold air transferring assembly includes a cooling plate and a cooling radiator, and the cooling plate is in thermal contact with the cooling surface. The hot air transferring assembly includes a cooling plate and a cooling radiator, and the cooling plate is in thermal contact with the heat releasing surface. The storage space is divided into a cold chamber and a hot chamber by the thermoelectric cooler and the cooling plates.