Tiansheng nian gaiding xinlü 天盛年改定新律 "New penal law revised during the Tiansheng reign (1149-1169)" is the surviving law code of the Western Xia dynasty 西夏 (1038-1227).
The 20 chapters (zhang 章, one is lost) contain 1,460 law articles.
In 1909 Pyotr K. Kozlov (1863-1935), leader of a Russian expedion to the western part of China explored the ruins of Kara-Khoto (Chinese: Heicheng 黑城) where he found a lot of documents which he took with him back to Russia. The law code of the Western Xia is stored today in St Petersburg and has not been published to date. It is a very important source for the administrative and social history of the Western Xia empire which still awaits further research.