The present invention relates to a portable heat transfer unit for supplying heat to an external thermal load such as a heater or a heating cloth and available even in the outdoor where supply of electric power or gas is difficult, in which combustion is enabled under good state by controlling the mixing ratio of LPG and air. In the portable heat transfer unit, mixture gas supplied from a gas/airmixer having an LPG gas supply (1) and a mixing ratio regulation mechanism (2) is ignited by a piezoelectric ignition mechanism and flame-burned in a combustion chamber (4), a heat drive pump (6) installed with a heat collection container (5) interposed is driven by generated heat and heat is transmitted to an external thermal load. The mixing ratio regulation mechanism can be controlled by usinga spring timer (16) actuated by an operating lever (13) or by operating a temperature sensor for regulating mixing ratio provided in the heat collection container.