A heat exchanger, comprising: a set of first heat exchange tubes; a set of second heat exchange tubes; and a set of fins each of the at least multiple fins in the set of fins has a first part and a second part, with at least multiple fins in the set of fins being in contact with at least multiple first heat exchange tubes in the set of first heat exchange tubes and at least multiple second heat exchange tubes in the set of second heat exchange tubes simultaneously, wherein the width of each fin is the sum of the width of the first heat exchange tube, the width of the second heat exchange tube and a gap between the first part and the second part, characterized in that the set of first head exchange tubes form a first circuit and the set of second heat exchange tubes form a second circuit, wherein the first circuit and the second circuit are different circuits and the at least multiple first heat exchange tubes in the set of first heat exchange tubes, the at least multiple second heat exchange tubes in the set of second heat exchange tubes and the at least multiple fins in the set of fins are arranged in an arrangement direction such that: the at least multiple first heat exchange tubes are respectively arranged at th positions, M1 = 4n - 3; the at least multiple second heat exchange tubes are respectively arranged at th positions, M2 = 4n - 1; and the at least multiple fins are respectively arranged at Nth positions, N = 2n, where n is a positive integer. a set of first heat exchange tubes; a set of second heat exchange tubes; and a set of fins each of the at least multiple fins in the set of fins has a first part and a second part, with at least multiple fins in the set of fins being in contact with at least multiple first heat exchange tubes in the set of first heat exchange tubes and at least multiple second heat exchange tubes in the set of second heat exchange tubes simultaneously, wherein the width of each fin is the sum of the width of the first heat exchange tube, the width of the second heat exchange tube and a gap between the first part and the second part, characterized in that the set of first head exchange tubes form a first circuit and the set of second heat exchange tubes form a second circuit, wherein the first circuit and the second circuit are different circuits and the at least multiple first heat exchange tubes in the set of first heat exchange tubes, the at least multiple second heat exchange tubes in the set of second heat exchange tubes and the at least multiple fins in the set of fins are arranged in an arrangement direction such that: the at least multiple first heat exchange tubes are respectively arranged at th positions, M1 = 4n - 3; the at least multiple second heat exchange tubes are respectively arranged at th positions, M2 = 4n - 1; and the at least multiple fins are respectively arranged at Nth positions, N = 2n, where n is a positive integer. the at least multiple first heat exchange tubes are respectively arranged at th positions, M1 = 4n - 3; the at least multiple second heat exchange tubes are respectively arranged at th positions, M2 = 4n - 1; and the at least multiple fins are respectively arranged at Nth positions, N = 2n, where n is a positive integer.