Nader Bohlooli - PhD- Department of manegment, bonab Branch, Islamic Azad University, bonab, Iran
Taghi Mohammadi - PhD Student- Department of manegment, Ghareh Ziaaddin Branch, Islamic Azad University, Ghareh Ziaaddin, Iran

The present paper aims to investigate the relationship between product-market competition and bankruptcy in companies listed on the stock exchange of Tehran. For this purpose, the Herfindahl index (also known as Herfindahl–Hirschman Index, or HHI) and Falmer’s model have been considered as the measures of competition and bankruptcy, respectively. Hypotheses were tested during the period 2007-2013. The research population consists of companies listed on the stock exchange of Tehran, from which 155 companies were selected as samples using elimination selection method. Multivariable linear regression model has been used to assess the research samples. The results of the research show that there is a positive significant relationship between product-market competition and bankruptcy; namely, the probability of bankruptcy increases as a result of increasing product-market competition and it decreases by the reduction of product-market competition.

product-market competition, bankrupt,Iiran