A conventional Stern‐Gerlach separation of hydrogen molecules is proposed for the supplying of a radio‐frequency or PIG ion source of standard type to produce microampere beams of polarized protons for acceleration in electrostatic accelerators, cyclotrons, etc. The long nuclear relaxation time of molecular hydrogen gas allows the accumulation of polarized protons (as molecules) for the production of microampere average beams by means of a pulsed ion source. The polarized protons after acceleration have the energy‐ and angular‐spread characteristic of the machine with which they were accelerated. There is no apparent reason why polarized H−may not be produced in the same strong‐field rf ion source, accelerated in a weak field to preserve polarization and stripped in a tandem machine, all without significant depolarization.