Cyclic oligomers composed of triphenylamine backbone were conveniently prepared via palladium-catalyzed one-pot synthesis. The condition for the preparation was optimized to give the cyclic oligomers with large ring sizes in good yield up to 73.7%. The type of base for the reaction dramatically influenced the yield of cyclic oligomers, and potassium tert-butoxide was the most effective for the cyclization. The composition of the cyclic oligomers was determined by high-performance liquid chromatography (H PLC) as a mixture of pentamer, hexamer, and heptamer. The cyclic pentamer was easily isolated by only recrystallization from tert-butyl methyl ether.