Wide fluctuations of the prices of chicken and egg along with the containment of these fluctuations always matter to producers, consumers and government. These fluctuations are affected by various factors on the supply and demand sides of the product and its inputs. The results of this research are as follows: Contributing 1.5 and 1 per cent to the world production of chicken (76.3 million tons) and egg (61.3 million tons) respectively, Iran is of eighteenth and seventeenth ranks in the world.By comparing domestic and foreign prices of chicken on a floating exchange rate basis during 1991-2005, it is found that the domestic price has been always lower than world price by 1999 but higher afterwards. However, the domestic price of egg has been always lower than its world price. A review of the monthly retail prices of chicken and egg during 1370-84 also suggests that both products have followed a similar price trend. In fact, prices have the highest growth in spring with a slow increase in summer, resurgence in autumn and the lowest growth in winter. In addition to price fluctuations, the most important challenges to Iran's poultry farming are high production costs, long period of production, feed-to-chicken coefficient, and dependence of the poultry farming on input importation, especially feed. According to our findings, in the egg market, 1, 4, 8 and 16 enterprise concentration ratios have been respectively 1.94, 6.58, 10.868 and 17.05 per cent in 1384. Therefore, the market structure of egg production has been competitive. Oneenterprise concentration ratio has reduced from 3.2 per cent in 1375 to 1.94 per cent in 1385. Herfindahl index of egg market was about 0.005 in 1375 but reduced to 0.003 in 1384, implying an increased competition in market structure. During 1379- 83, Lerner indices of domestic markets of chicken and egg, in comparison with their export markets, have increased from 0.06 and 0.13 to 0.43 and 0.37 respectively, reflecting an increased competition in export market structures of chicken and egg.