On March 29, the judge ordered Kavalenka to pay 1 million Belarusian rubles ($115) for verbally insulting police after being stopped on March 25 for allegedly crossing a street at an improper place.
That day, activists were marking the 95th anniversary of the establishment of an independent Belarusian state in 1918.
Kavalenka made headlines last year for his hunger strikes over a three-month period while in prison.
In February 2012, he was given a 25-month sentence for violating the terms of his parole for a conviction on charges of "illegally displaying the banned Belarusian national flag."
He was released in September.