Vacuum arc ion source is suitable for miniaturized pulse neutron generator because of its simple structure and high deuterium ion density. A small vacuum arc ion source is developed with the diameter of 20 mm and the length of 25 mm. TiD works both as the cathode and as deuterium source, which avoids using the complicated gas pipes. The light spots caused by the ion source are measured by a Charge Coupled Device(CCD) camera. It is found that the larger the arc current, the brighter the spots. The saturated ion current is measured by a biased plate. When the arc current is larger than 100 A, the saturated ion current could be above 1 A. The deuterium ion ratio in the plasma is measured by a simple magnetic analysis. The ratios grow with the arc current, and the maximum is about 27%. When the arc current is 100 A and the pulse duration is 5 μs, the neutron yield is about 1×105 n for the TiD target under 120 kV voltage. The source can be used in small pulsed neutron generators suitably.