Authorities later imposed a curfew on the impoverished city, where tensions have been high since Saturday when a young unemployed man suffered a fatal electric shock during a protest.
"Work is a right," chanted those at Tuesday's demonstration, who numbered 500 according to an AFP correspondent and twice as many according to an interior ministry official.
"Some threw stones while others climbed on the roof of the governor's office. Police dispersed them by firing tear gas," said the ministry official.
Protesters were seen setting alight tyres which they used to block one of the main roads of the city, as the army was deployed outside the governor's office.
The interior ministry said calm was restored later in the day.
But in the afternoon the ministry announced an overnight curfew would be imposed on Kasserine from 6:00 PM until 5:00 AM starting on Tuesday, but it was not clear if it would be extended.