Processing and properties of a dome-shaped piezoelectric transformer with a composition of 0.03Pb(Sb0.5Nb0.5)O3-0.03Pb(Mn1/3Nb2/3)O3-0.465PbTiO3-0.475PbZrO3 have been investigated. A dome-shaped sample was fabricated by powder injection molding. The dimension of the dome-shaped sample was a 28 mm in diameter and 2.1mm in thickness with a curvature radius of 18 mm. Finite element modeling for the complicated piezoelectric transformer was applied to simulate vibration mode in the sample. The high power characteristics of a dome-shaped piezoelectric transformer were examined by the lighting test for a 55W PL lamp. The 55W PL lamp was successfully driven by the dome-shaped piezoelectric transformer with sustaining efficiency higher than 98%. The transformer with ring/dot area ratio of 2.1 exhibited the maximum properties in terms of output power, efficiency and temperature stability.