Urban　development　assessment　is　helpful　for　urban　planning　and　urban　development　policies.　Census,　survey,　and　nighttime　light　remote　sensing　data　have　been　widely　used　to　measure　the　urban　development　in　previous　research.　However,　most　studies　only　focused　on　the　size　of　urban　development　in　a　specific　period　and　few　of　them　have　simultaneously　considered　the　size　and　speed　of　urban　development.　A　model　that　considers　both　the　size　and　speed　of　urban　development　is　necessary　for　evaluating　the　level　of　urban　development,　which　is　a　dynamic　process.　On　the　basis　of　the　nighttime　light　data　of　Suomi　NPP-VIIRS　from　2012　to　2019,　the　nighttime　light　kinetic　energy　index　is　proposed　to　measure　the　kinetic　energy　of　urban　development　by　considering　the　size　and　speed　of　urban　development.　Then,　the　Dynamic　Time　Warping　(DTW)　algorithm　was　utilized　to　measure　the　DTW　distance　using　the　nighttime　light　kinetic　energy　index.　Finally,　328　cities　in　China　were　classified　according　to　the　DTW　distance.　Numerically,　the　nighttime　light　kinetic　energy　index　in　most　cities　increased　significantly　from　2013　to　2019,　especially　in　the　southeast　coastal　areas　and　central　regions,　and　that　in　the　northwest　area　has　also　increased　greatly.　In　terms　of　spatial　distribution,　the　original　urban　agglomerations　composed　of　cities　with　high　night-time　lighting　kinetic　energy　index　values　expanded　from　2013　to　2019.　The　328　cities　were　divided　into　five　levels.　The　classified　levels　are　more　comprehensive　and　reasonable　than　the　city　rank　released　by　First　Finance　in　2019.　The　Yangtze　River　Delta　urban　agglomeration　was　taken　an　example　to　analyze　the　synergy　of　urban　agglomeration　development,　revealing　that　Tongling,　Chizhou,　and　other　cities　in　Anhui　province　still　has　a　weak　connection　with　the　Yangtze　River　Delta　urban　agglomeration.　The　development　of　a　hinterland　city　(such　as　Wuhu,　Ma＇anshan)　is　recommended　to　link　these　cities.　©　2021,　Science　Press.　All　right　reserved.