Power system outages can lead to huge economic losses for various industries. Jeju island power system outage in 2006 also caused significant social and economic impacts in Korea. There have been numerous attempts to evaluate the economic costs of power system outages. Power system outages can also have financial impacts on electric power industry. This paper attempts to analyze the economic impacts of the 2006 Jeju island power system outage on the values of the firms in the power industry using event study. Empirical analysis results are presented to show the economic impacts of the 2006 Jeju island outage on the values of the firms in the power industry.