A heat exchanger comprising a first heat exchange row and a second heat exchange row overlapping with each other, wherein each heat exchange row (10, 20) comprises a first distributor (11, 21) and a second distributor (12, 22) and a plurality of parallel, coplanar tubes (13, 23) interconnecting the first distributor (11, 21) and the second distributor (12, 22), wherein each of said distributors (11, 21, 12, 22) has a tubular body, on a lateral wall (11a, 21a, 12a, 22a) of which a plurality of slots is formed, in each of which slots one end of a relevant tube (13, 23) is inserted, wherein one of said first distributor and second distributor of the first heat exchange row has an inlet of the heat exchanger and one of said first distributor and second distributor of the second heat exchange row has an outlet of the heat exchanger, wherein the heat exchanger further comprises a fluid connection element (40"; 40′′′) connecting one of said first distributor and second distributor of the first heat exchange row, hereinafter referred to as the first row distributor, to one of said first distributor and second distributor of the second heat exchange row, hereinafter referred to as the second row distributor, wherein said fluid connection element is an element (40"; 40′′′) which is fixedly connected at the top to ends (11e, 21e) of the first row distributor and of the second row distributor and in which a conduit is formed that fluidically connects the first row distributor to the second row distributor, wherein the fluid connection element (40"; 40′′′) is formed as a hollow plug inserted into the ends (11e, 21e) of the first row distributor and of the second row distributor, characterized in that respective notches (11n, 21n) are formed on the lateral walls (11a, 21a) of the first row distributor and of the second row distributor, at the ends (11e, 21e) of the first row distributor and of the second row distributor, in which notches the fluid connection element is inserted. wherein each of said distributors (11, 21, 12, 22) has a tubular body, on a lateral wall (11a, 21a, 12a, 22a) of which a plurality of slots is formed, in each of which slots one end of a relevant tube (13, 23) is inserted, wherein one of said first distributor and second distributor of the first heat exchange row has an inlet of the heat exchanger and one of said first distributor and second distributor of the second heat exchange row has an outlet of the heat exchanger, wherein the heat exchanger further comprises a fluid connection element (40"; 40′′′) connecting one of said first distributor and second distributor of the first heat exchange row, hereinafter referred to as the first row distributor, to one of said first distributor and second distributor of the second heat exchange row, hereinafter referred to as the second row distributor, wherein said fluid connection element is an element (40"; 40′′′) which is fixedly connected at the top to ends (11e, 21e) of the first row distributor and of the second row distributor and in which a conduit is formed that fluidically connects the first row distributor to the second row distributor, wherein the fluid connection element (40"; 40′′′) is formed as a hollow plug inserted into the ends (11e, 21e) of the first row distributor and of the second row distributor, characterized in that respective notches (11n, 21n) are formed on the lateral walls (11a, 21a) of the first row distributor and of the second row distributor, at the ends (11e, 21e) of the first row distributor and of the second row distributor, in which notches the fluid connection element is inserted.