In large-scale energy storage and transportation applications, a comprehensive understanding of the evaporation characteristics of liquid methane will benefit the extension of liquid methane storage duration and the improvement in energy storage efficiency. The complexities of achieving cryogenic steady-state evaporation and submillimeter visualization make experimental studies of liquid methane interfacial heat and mass transport difficult and insufficient. In this study, a cryogenic evaporation testing rig was constructed to obtain the interfacial temperature distributions of liquid methane with a spatial resolution of 50 µm. The evaporation coefficient was obtained directly from the measured temperature profile data near the liquid/vapor methane interface. The coupled effects of thermal conduction and Marangoni convection at the liquid-methane interface were revealed and quantitatively compared to those of liquid oxygen and water. A new high-precision dimensionless correlation for the evaporation coefficient was proposed for liquid methane, which explained the consistent dependence of the evaporation coefficient on the liquid-side temperature and wall interface height. The results help to enhance the simulation stability and accuracy and benefit the design of liquid methane or liquefied natural gas storage tanks.