Laos is a mountainous country with a road network that is prone to the impact of landslides. The development and maintenance of the transport sector are seen as imperatives in the country's socio-economic growth, and landslides pose a potential constraint on this development. This paper describes a landslide vulnerability assessment undertaken for a significant proportion of the country's mountain road network for maintenance management and investment decision-making purposes. Limited desk study data meant that the focus of the study was on the collection of landslide location and impact data in the field and was able to benefit from the effects of the 2018 wet season during which record rainfalls were recorded in some locations. A simple index of vulnerability was developed and combined with engineering geological observation to yield a composite output that comprised tabular data and maps, along with broad recommendations for risk and engineering management.