"I didn't expect such [a] sentence," Letchkov, who is the Bulgarian Football Union (BFU) vice-president, told reporters. "We'll appeal, of course, because I think it was a political act."
The BFU was not immediately available to comment.
Letchkov, who scored the winning goal in Bulgaria's famous 2-1 quarter-final victory over Germany at the 1994 World Cup, was found guilty of mismanagement which caused significant damage to the Sliven municipality, the court said.
Last year, Letchkov, 44, was removed from the post of Sliven mayor over charges related to abuse of power but was restored two months later.
The three-year sentence was suspended for five years.
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