The Aizu Railway Aizu Line (会津鉄道会津線, Aizu Tetsudō Aizu-sen) is a 57.4 km (35.7 mi) long railway line from Nishi-Wakamatsu Station in Aizuwakamatsu to Aizukōgen-Ozeguchi Station in Minamiaizu, Fukushima, Japan.

The electrified southern part goes beyond the Aizukōgen-Ozeguchi terminus onto the Yagan Railway Aizu Kinugawa Line, Tobu Railway and JR East all the way to Tokyo.

The non-electrified northern part runs a diesel service beyond Nishi-Wakamatsu Station to Aizu-Wakamatsu Station on the JR East Tadami Line.

The Aizu Line was constructed between 1927 and 1953 by the Japanese National Railways (JNR) as part of a plan to build a direct line from Aizu-Wakamatsu to Tokyo.

The Aizukōgen-Ozeguchi - Aizu-Tajima section was electrified at 1500 VDC in 1990 to facilitate through-running onto the Kinugawa line.