Electric　Vehicles　(EVs)　are　becoming　more　and　more　popular　in　our　daily　life,　which　replaces　traditional　fuel　vehicles　to　reduce　carbon　emissions　and　protect　the　environment.　EVs　need　to　be　charged,　but　the　number　of　charging　piles　in　a　Charging　Station　(CS)　is　limited,　and　charging　is　usually　more　time-consuming　than　fueling.　According　to　this　scenario,　we　propose　a　secure　and　efficient　charging　scheduling　system　based　on　a　Directed　Acyclic　Graph　(DAG)-blockchain　and　double-auction　mechanism.　In　a　smart　area,　it　attempts　to　assign　EVs　to　the　available　CSs　in　the　light　of　their　submitted　charging　requests　and　status　information.　First,　we　design　a　lightweight　charging　scheduling　framework　that　integrates　DAG-blockchain　and　modern　cryptography　technology　to　ensure　security　and　scalability　during　performing　scheduling　and　completing　tradings.　In　this　process,　a　constrained　multi-item　double-auction　problem　is　formulated　because　of　the　limited　charging　resources　in　a　CS,　which　motivates　EVs　and　CSs　in　this　area　to　participate　in　the　market　based　on　their　preferences　and　statuses.　Due　to　this　constraint,　our　problem　is　more　complicated　and　harder　to　achieve　truthfulness　as　well　as　system　efficiency　compared　to　the　existing　double-auction　model.　To　adapt　to　it,　we　propose　two　algorithms,　namely,　Truthful　Mechanism　for　Charging　(TMC)　and　Efficient　Mechanism　for　Charging　(EMC),　to　determine　an　assignment　between　EVs　and　CSs　and　pricing　strategies.　Then,　both　theoretical　analysis　and　numerical　simulations　show　the　correctness　and　effectiveness　of　our　proposed　algorithms.