The sintering phenomena, electrical resistivity, dielectric and piezoelectric properties of lead titanate ceramics modified by the partial substitution of La for Pb and Mn for Ti, (Pb1-1.5xLax)(Ti1-yMny)O3 ceramics, have been investigated. In (Pb1-1.5xLax)(Ti1-yMny)O3 system, with increasing lanthanum content, the realtive bulk density increased, but the Curie point and tetragonality (c/a) decreased. The tetragonal-to-cubic phase transition boundary existed in the range of 0.20<x<0.25. The electromechanical anisotropy (kt/kp) was observed in the tetragonal region and electromechanical coupling factor (k1) had a maximum value at x=0.05. In (Pb1-1.5xLax)(Ti1-yMny)O3 system, the electromechanical coupling factor (k1) and electrical resistivity had maximum values at y=0.01, but dielectric constant and dissipation factor had minimum values. It was concluded that lanthanum enhanced the sinterability of lead titanate and MnO2 improved the piezoelectric properties.