Natural　gas　hydrate　(NGH)　mining　via　CH4/CO2　exchange　integrates　CH4　extraction　with　CO2　geological　sequestration,　thereby　facilitating　the　achievement　of　carbon　neutrality.　However,　the　relatively　low　replacement　cost　remains　a　significant　bottleneck　that　hinders　its　large-scale　application.　In　this　study,　we　investigated　the　potential　of　intermittent　ultrasonic　assistance　to　enhance　CH4/CO2　replacement　in　hydrate-bearing　sediments.　The　effects　of　ultrasonic　power,　experimental　pressure,　and　temperature,　as　well　as　initial　water　and　hydrate　saturations,　were　systematically　analyzed.　Results　demonstrated　that　both　CH4　recovery　and　CO2　sequestration　rates　exhibited　an　increasing　trend　with　higher　ultrasonic　power.　Specifically,　at　100%　ultrasonic　power,　the　CH4　recovery　and　CO2　sequestration　rates　reached　79.06%　and　55.94%,　respectively.　Additionally,　both　rates　increased　as　the　pressure　decreased　and　the　temperature　rose.　Notably,　ultrasonic　assistance　significantly　improved　CH4/CO2　replacement　even　under　conditions　where　the　experimental　pressure　exceeded　the　CH4　hydrate　phase　boundary,　or　the　temperature　was　below　the　freezing　point.　Increased　initial　water　saturation　was　found　to　be　beneficial　for　the　ultrasonic-assisted　CH4/CO2　replacement,　whereas　a　higher　hydrate　saturation　negatively　impacted　the　process.　These　findings　provide　valuable　insights　into　enhancing　CH4/CO2　swapping　and　contribute　to　the　advancement　of　NGH　mining　and　CO2　geological　sequestration　technologies.　©　2025　American　Chemical　Society.