| Country: | CHN |
| Province: | Henan |
| Type: | S |
| Route: | 37 |
| Alternate Name: | Lanxu Expressway Chinese: 兰许高速公路 |
| Length Km: | 120 |
| Established: | 2005 |
| Direction A: | Northeast |
| Direction B: | Southwest |
| Terminus A: | Lankao West Interchange connecting in Lankao, Kaifeng, Henan |
| Junction: | in Xiangfu District, Kaifeng in Tongxu County, Kaifeng in Weishi County, Kaifeng in Weishi County, Kaifeng in Yanling, Xuchang (under construction) |
| Terminus B: | Xuchang East Interchange connecting in Jian'an District, Xuchang |
The Lankao–Xuchang Expressway, often abbreviated as Lanxu Expressway and designated as S37 in Henan's expressway system, is a 114km (71miles) long regional expressway in Henan, China. Currently it's fully completed.
Before July 8, 2024, this expressway was a part of Lannan Expressway which started at Lankao and ended at Nanyang. The first phase of the expressway is from Xuchang to Nanyang via Pingdingshan and was called as Xupingnan Expressway . This section was opened on 12 December 2004 and provided expressway connections to the above-mentioned three major cities in Henan.[1] The second phase (Lankao–Xuchang section, called Lanxu Expressway) was opened on 19 November 2005.[2] The third phase was opened on December 19, 2005.[3] [4]
The Xuchang–Ye County section has also been designated as G0421.
On July 8, 2024, the latest version of Henan Expressway numbering was released by Henan Provincial Department of Transportation.[5] The previous Henan S83 (Lankao–Nanyang Expressway) was abolished. Instead, the Ye County-Nanyang section was redesignated as G3612, and the name Lanxu Expressway was restored on Lankao-Xuchang section.
From northeast to southwest: