RFX

RFX may refer to:
 * Reversed-Field eXperiment, a reversed field pinch nuclear fusion device
 * The collective term for a request for information (RFI), request for proposal (RFP), or request for quotation (RFQ)
 * J P Hunt Air Carriers (ICAO airline code: RFX) aka REFLEX, U.S. airline: see List of airline codes (J)
 * The regulatory factor X (RFX) gene and protein family:
 * RFX1 gene and protein
 * RFX2 gene and protein
 * RFX3 gene and protein
 * RFX4 gene and protein
 * RFX5 gene and protein
 * RFX6 gene and protein