Experimental data on evaporation in a 7-mm-diameter microfin tube are presented. The data were taken at three different evaporation temperatures (2°C, 6°C, and 10°C, respectively). The mass flux was between 100 and 300 kg/m2·s and the heat flux between 7 and 12.4 kW/m2. Data were presented in the form of local heat transfer and frictional pressure gradient. The effect of heat flux, mass flux, and pressure on the heat transfer coefficient are reported in the present investigation.