EXHIBIT 11 FIRST KEYSTONE CORPORATION COMPUTATION OF EARNINGS PER COMMON SHARE For the Three Month Period Ended June 30, 2003 and 2002 (Dollars in Thousands) 2003 2002 <s> <c> <c> Primary Net Income $ 3,635 $ 3,391 Shares Weighted average number of common shares outstanding 2,956,433 2,975,180 Adjustments - increases or decreases None None Weighted average number of common shares outstanding as adjusted 2,956,433 2,975,180 Primary earnings per common share $ 1.23 $ 1.14 Assuming full dilution Net Income $ 3,635 $ 3,391 Shares Weighted average number of common shares outstanding 2,964,592 2,978,542 Adjustments - increases or decreases None None Weighted average number of common shares outstanding as adjusted 2,964,592 2,978,542 Earnings per common share assuming full dilution $ 1.23 $ 1.14 25