A dielectric anomaly above the Curie temperature of lead iron tungustate Pb(F $e_{2}$3/ $W_{1}$3/) $O_{3}$ may be related to interfaces at grain boundary. The origin of the anomalous dielectric properties is not clear. The La-substituted lead iron tungstate P $b_{(1-x)}$ L $a_{x}$ (F $e_{(2+x)}$ 3/ W(sub (10x)/3/) $O_{3}$ ceramics were prepared for the purpose of investigating this anomaly. The dielectric anomaly at around 300K may be explained by electrical conduction form F $e^{3+}$ to F $e^{2+}$ in the interfaces of grain boundary on the basis of complex inpedance analysis. Furthermore, Mossbauer spectrum shows the existence of F $e^{+2}$ ions.s.s.