A loom(1) with a filling bar preventing function comprises two or more filling bar preventing devices (21) , and a filling bar prevention data setting unit (20) that gives set values of filling bar preventing parameters to the two or more filling bar preventing devices (21). Set values for degrees of filling bars to be given to the filling bar preventing devices (21) are stored beforehand in the filling bar prevention data setting unit (20). Filling bar information about an expected degree of filling bars is given to the filling bar prevention data setting unit (20). The filling bar prevention data setting unit (20) selects the set values corresponding to the filling bar information given thereto, and gives the selected set values respectively to the filling bar preventing devices (21). The loom (1) operates according to the expected degree of filling bars to prevent the formation of filling bars effectively.