We have measured the magnetic and superconducting properties of the intermetallic compounds Y1-xRExPd5B3C0.4 (RE = Er, Ho, Dy, Gd; 0 less than or equal to x less than or equal to 1.0) over wide temperature and magnetic field ranges. The magnetic pair breaking effect is the major mechanism causing the reduction of the T-c. The small value of the Curie-Weiss temperature suggests the coupling between the conduction electrons and the magnetic moment is not strong. The anomalous resistivity in the superconducting state is considered to be due to the occurrence of the long range magnetic ordering of the RE+3 moments. The inter-site interaction between RE3+ local moments is attributed to the Ruderman-Kittel-Kasuya-Yosida indirect exchange interaction via conduction electrons
