Primary chick embryo cells (CEC), cultured in vitro, produce interferon (IFN) following alcohol treatment. Brief exposure of cells to methanol, ethanol, 2-propanol, or butanol resulted in the production of an acid-labile IFN which could be detected in the supernatant medium as early as 60 min after removal of the drug. Following “priming„ of the cells by homologous IFN,(1) these four alcohols induced even greater yields of IFN: up to 4,000 units per 107 cells of an acid-stable IFN were detected. In contrast, priming of CEC with IFN had no effect on the yield of IFN induced by a standard viral inducer, avian reovirus. Maximal IFN production by ethanol in IFN-primed cells depended on both the priming dose of IFN and length of contact with the cells, as well as the in vitro age of the cell cultures. Complete neutralization by polyclonal anti-chick IFN serum, of both the acid-labile and acid-stable preparations induced by ethanol treatment confirmed that both were chicken IFNs. This report describes the general characteristics of IFN induction in primary chick embryo cells by alcohols, with particular emphasis on ethanol, chemically the simplest IFN inducer reported to date. © 1991, Mary Ann Liebert, Inc. All rights reserved.