Road network development in Thailand aims to improve social and economic development; however, road development can lead to land-cover change. The purpose of this research is to investigate the relationships among road network development, its connectivity, and change of landcover. Fifty-six intensive study areas (ISAs) depicting each stage of the road network development were selected and divided into four groups. Network analysis and graph theory-based network indices were used for determining road connectivity. Land cover information derived from Landsat images was classified into seven classes: forest, water, plantation, rice, upland crops, built-up areas, and clouds. Road network connectivity and land-cover for each group were compared using statistical analysis including Kendall’s Tau and Wilcoxon matched pair tests. The results showed that improvement of road connectivity contributes to significant changes in the amount of forests, upland crops, and plantation.