Samples with a nominal composition of Hg 1−x Pb x Ba 2 Ca 2 Cu 3 O 8+δ (x~0.1, 0.2, and 0.3) have been synthesized and characterized. The Pb-doping promotes the formation of the three CuO2-layer compound Hg 1−x Pb x Ba 2 Ca 2 Cu 3 O 8+δ, and reduces the release of Hg vapor at the synthesis temperature. The intergrain electric coupling is also significantly enhanced by the doping, resulting in lower normal-state resistivity and higher intergrain critical current density. The carrier concentration of the as-synthesized samples increases with the increase of x, ranging from underdoped (x~0) to overdoped (x≥0.2).