The　development　of　industry　has　promoted　theprogress　of　civilization.　The　process　of　refrigeration　and　cooling　in　the　industry　is　an　indispensable　part.　With　the　development　and　progress　of　industrial　technology,refrigeration　and　cooling　technology　accompanied　by　it　is　also　advancing　with　the　times.　This　chapter　introduces　the　characteristics　of　refrigeration　and　cooling　needs　in　theindustry,　and　the　thermodynamic　characteristics　of　refrigeration　systems　in　the　industry.　The　chapter　also　presents　examples　of　CO2　cooling　system　applications　in　fourapplication　areas:　food　industry　cooling,　ice　making　in　ice　rink,　power　generation　with　refrigeration,　and　transport　refrigeration.　©　2023,　Springer　Nature　Switzerland　AG.