The authors have tested 154kV-class transmission line arresters by installing them on an instrumented tower of a double circuit test transmission line during winter seasons since 1993. The tower is struck by natural and artificially-triggered lightning several times during each winter season. First, the authors verified the conventional transmission line arrester designed against summer lightning was effective against winter lightning. Next, the authors investigated its applicability against winter lightning based on EMTP analysis taking account of observed lightning current waveforms in winter, and developed a new transmission line arrester of reduced rating. The new arrester of reduced rating was tested on the test line and showed no damages in appearance and in characteristics by the inspection after field test. The new arrester for 154kV line will perform well against winter lightning when the tower footing resistance is 30Ω or less.