Nabulsi soap was traditionally made by women for household use before the 10th century. By the 14th century the industry of soap making thrived in the city of Nablus and the Nabulsi soap became widely used in the Middle East and Europe along with Savon de Marseille.

Ingredients of Nabulsi soap are virgin olive oil, water, and an alkaline sodium compound. The compound is made by mixing the powdered ashes of the barilla plant, which grows along the banks of the River Jordan, with locally supplied lime. The sodium compound is then heated with water and olive oil in large copper vats over fermentation pits. The solution of water and sodium compound becomes increasingly concentrated in a series of 40 cycles repeated over eight days. During that time, a wooden tool known as a dukshab is used to stir the liquid soap continuously. The liquid soap is then spread in wooden frames to set. After setting, it is cut and the soap cubes are left to dry for a year. Workers stack them in ceiling-high structures resembling cones with hollow centers that allow the air to circulate around them.
The finished product is ivory-colored and has almost no scent.