Abstract: The main results measured on the H~- preinjector used in DESY are presented.18keV, 60--80mA of pulsed H~- current can be extracted from the magnetron H~-source. It is discovered that an outside magnetic field can induce a magneticfield inside of a solenoid magnet. The time for space charge neutralizationalong the LEBT is～100 μs. After being focused by two solenoids and acceleratedby RFQ, pulsed H~- beam of 750±8.8 keV in energy, 52 mA in current, 0.8 ns inbunch width, and 3 mm.mrad in emittance can be obtained, when the extractedbeam current from the source is～65mA. More than 33 mA of the acceleratedcurrent is within 1 mm.mrad of emittance.