The La'uo system (Hui sen La'uo) is a planetary system in the Xi'an Empire (SaoXy'an) that consists of a red giant, three terrestrial planets, two asteroid belts, and a gas giant. In MXY III.1017 (SEY 2759), a group of Xi'an outlaws discovered a jump point from the Ē'aluth system into La'uo and made it into their base of operations. Although the Xi'an government learned of the system's existence soon afterwards, they declined to claim it due to its lack of terraformable planets. It became a part of the Perry Line in MXY III.1026 (SEY 2771) when the UEE military detected a jump point from the Tohil system system to La'uo, forcing the outlaws that lived there to flee as military ships from both sides of the Xi'an-Human Cold War flooded in and took their place.
In MXY III.1040 (SEY 2789), Emperor T.uēng se Kr.ē traveled through La'uo on his way to the Tohil system, where he and Senator Terrence Akari of the United Empire of Earth (UEE) negotiated the terms of what would become known as the Akari-Kr.ē treaty. The same pirate gangs who once lived in La'uo played a key role in ensuring that Kr.ē could pass through the system and into Tohil undetected. In return, Kr.ē recognized these pirate gangs as nyayu'a and granted them dominion over the La'uo system with the exception of the planet Yengchuai (La'uo II).