1140s in Japan

was a after Kōji and before Kyūan. This period spanned the year from February 1144 through July 1145. The reigning emperor was .

, also romanized as Kyū-an, was a after ''Ten'yō and before Ninpei.'' This period spanned the years from July 1145 through January 1151. The reigning emperor was .

was a after Chōshō and before Eiji. This period spanned the years from September 1135 through July 1141. The reigning emperor was .

Japanese era from July 1141 to April 1142

Japanese era from April 1142 to February 1144