According　to　the　characteristics　of　the　permanent　magnetic　field　for　room　temperature　magnetic　refrigerator,　a　set　of　calculation　formula　are　derived　from　using　magnetic　Coulomb＇s　law.　Based　on　the　formula,　the　magnetic　flux　density　of　permanent　magnetic　paths　for　various　room　temperature　of　magnetic　refrigerators　can　be　calculated.　The　magnetic　flux　density　calculated　by　the　formula　is　fairly　consistent　with　the　one　measured　by　experiment.　The　permanent　magnetic　field　over　1.8　T　is　designed　by　using　the　magnetic　focusing　technique.　Several　permanent　magnetic　fields　are　designed　for　the　reciprocating　and　rotating　magnetic　refrigerators　at　room　temperature.