We examine the 12 recession periods from 1954 to 2010 in Taiwan, which announced by the National Development Council. We use 14 economic indicators to verify the recession periods. The main results are as follows. (1) The 12 recessions should be changed to 14 recessions. (2) We divide the economic indicators into four types and find that the degree of the accuracy of the 12 recessions are, respectively, Production (50.1%), investment (64.3%), employment (67.5%) and consumption (70%). (3) The 7th, 8th, and 10th recessions are necessary to be modified. (4)We consider that National Development Council should add the two indicators, the Regular employees on payrolls in industry & services and the import volume of machinery and equipment and electronics, to the reference principle of recession.