Despite the recession in global financial markets, the Tehran stock Exchange experienced significant growth during the COVID-19 outbreak. Therefore, this article tries to solve this puzzle by analyzes the effect of three Coronavirus waves on the total index of Tehran stock Exchange, its sub-indices, and the different industries with daily data of Iran and the regression method with multiple breakpoints. The results show that each wave of COVID-19 have different effects on the stock market. COVID-19 in the first wave had a negative effect on the index of industries such as refined petroleum, chemical, Metals and transportation but had a positive effect on industries such as medicine and food. But in subsequent waves, response of different industries to the new pandemic is complicated for two reasons. First, the nominal exchange rate has positive and significant effect on main industries such as motor vehicles, banks, refined petroleum, metals and chemical (which have a considerable weight in the Tehran Stock Exchange), can show the positive trend of the index, especially in the first and second waves of the COVID-19. Second, the government\\\\\\\'s manipulation in raising the stock prices of these main industries to finance its budget deficit caused the Tehran Stock Exchange index to move in the opposite direction in some periods in response to the Corona virus.

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