Abstract: An ejector is configured to generate a high negative pressure capable of sucking and conveying fine metal pieces or chips, such as machinings or cuttings, for example, when using the ejector as a driving source for a fluid conveyor. The ejector includes a convergent-divergent nozzle having a throat formed between a suction port and a discharge port. Jet blowing holes are formed in the convergent-divergent nozzle to direct a jet stream from upstream of the throat to downstream of the throat, thereby forming a negative pressure. Pressure control holes open to the downstream of the jet blowing holes and are configured to communicate with a pressure space at a pressure level higher than a negative pressure formed by the jet stream and lower than a static pressure of the jet stream and the inside of the convergent-divergent nozzle.