The equilibrium vapor pressure of methylammonium bromide was measured as a function of temperature in the range of 433-503 K. Standard enthalpy and entropy of sublimation of CH3NH3Br at 298.15 K and 1 atm were determined as (196.7 +/- 2.8) kJ.mol(-1) and (280.0 +/- 5.6) J.mol(-1) K-1, respectively. The measured value of sublimation enthalpy was found to be in agreement with that directly calculated from the available thermodynamic data. Standard entropy of the crystalline CH3NH3Br at 298.15 K was determined for the first time as (160.2 +/- 5.6) J.mol(-1) K-1.