The history of Ciężkowice dates back to the year 1125, when in a document of Papal legate Gilles de Paris, the village is mentioned as a property of the Tyniec Benedictine Abbey. On February 29, 1348, King Kazimierz Wielki granted it Magdeburg rights town charter.
At that time, Ciężkowice was partly inhabited by the German settlers. In the late Middle Ages, Ciężkowice was located on a merchant route from the Kingdom of Hungary to Kraków.