The paramagnetic behavior of the oxyfluoferrites of spinel structure ZnxFe1-x [NiFe]O4-xFx (0 ⩽ x ⩽ 0, 80) has been investigated between the Curie point and 1300 K. The Neel's theory of ferrimagnetism allows to calculate the molecular fields factors which characterize the magnetic interactions. The results are compared to those obtained by Neel and Brochet for the ZnxFe1-x[Ni1+xFe1-x]O4 solid solution and an interpretation is given to the gradual change of the molecular field.