The magnetic moment of the proton has been measured by a method depending on the deflection of a beam of neutral hydrogen atoms in weak magnetic fields of sufficient inhomogeneity. When the field is of such magnitude that the nuclear spin is only partially decoupled from the electron spin the nuclear moment can be evaluated by measuring the atomic magnetic moments of the magnetic levels. Detection was effected on a molybdenum oxide coated plate and the results evaluated by the measurement of the widths and separation of the traces produced. A novel method of great convenience and simplicity for producing the proper magnetic field is described. The value of the proton moment obtained is 3.25+/-10 percent.