The microwave dielectric properties of new pyrochlore type oxides: Pb 3 R 3 Ti 7 Nb 2 O 26.5 (R=Y, Pr, Nd, Gd or Dy) have been presented in this paper. These compounds have cubic pyrochlore type structure. Microstructure of the sintered samples reveals well-formed grains in rod and round shapes. The dielectric properties of the materials were studied at low and microwave frequencies. They have relatively high dielectric constant ɛ r in the range 70–75 at 1MHz and ɛ r 62–68 range in the microwave frequency region (>3GHz). The quality factor (Qxf) of these compounds is moderate and best (3550) for Pb 3 Dy 3 Ti 7 Nb 2 O 26.5 compound in the microwave frequency region. This new series of lead containing pyrochlore type oxides having low-temperature sinterability are potential candidates for use as low-temperature cofired ceramic (LTCC) materials for microwave applications such as multilayer filters and other components.