Unmanned　aerial　vehicle　(UAV)　assisted　wireless　communications　has　received　a　lot　of　attention　in　recent　years　helping　to　support　high　traffic　flow　and　a　large　number　of　connected　wireless　devices.　Considering　that　intelligent　transportation　systems　(ITS)　are　latency-sensitive　and　require　reliable　delivery,　and　the　high　dynamic　topology　architecture　existing　in　vehicular　ad　hoc　networks　(VANETs),　UAV-assisted　VANET　become　as　an　effective　solution.　In　this　paper,　we　proposed　a　UAV-assisted　architecture　for　connected　and　autonomous　vehicles　(CAVs)　that　takes　the　benefits　of　flying　UAVs　to　achieve　the　closed-loop　control.　Then,　an　optimal　UAV-assisted　control　design　with　stochastic　communication　delays　is　proposed.　Numerical　simulations　demonstrate　that　the　proposed　control　approach　can　ensure　the　system　efficacy　and　control　stability.　©　2022　IEEE.