In　this　paper,　we　study　the　characteristics　of　the　spatial-temporal　pattern　of　land　used　for　transportation　at　the　county　level　since　the　implementation　of　the　reform　and　opening-up　policy　in　China　and　discuss　the　factors　that　influence　the　spatial　differences　between　lands　used　for　transportation　in　order　to　provide　a　reference　for　the　formulation　of　traffic　policies.　The　authors　used　ArcGIS　spatial　analysis,　an　ordinary　least　squares　(OLS)　regression　model,　and　a　geographic　detector　model　based　on　the　data　of　the　transportation　network　at　the　county　level　in　China　from　1978　to　2018.　We　obtained　the　following　results:　(1)　The　land　used　for　transportation　at　the　county　level　in　China　is　divided　by　the　Hu　Huanyong　Line,　which　is　characterized　by　spatial　variation,　where　the　southeastern　region　is　higher　than　the　northwestern　region.　(2)　Counties　with　a　high　proportion　of　land　used　for　transportation　show　obvious　changes,　characterized　by　the　transformation　from　the　＂corridor＂　zonal　distribution　of　arteries　to　the　＂diamond＂　group　distribution　of　major　city　clusters,　reducing　the　gap　in　land　used　for　transportation　at　the　county　level　in　China.　(3)　The　level　of　industrialization,　per　capita　gross　regional　product　(PGRP),　and　ratio　of　the　non-agricultural　working　population　all　have　an　incentivizing　impact　on　the　increase　in　land　used　for　transportation　at　the　county　level　in　China.　We　conclude　that　the　land　used　for　transportation　at　the　county　level　in　China　is　jointly　decided　by　the　economy,　industry,　and　population.　Therefore,　we　believe　that　it　is　necessary　to　promote　fast　economic　growth,　the　upgrading　of　industrial　structures,　and　population　density　to　achieve　the　balanced　development　of　land　used　for　transportation　at　the　county　level　in　China.