The two have been together for almost seven years but had to be separated in 2011 because they were having a lovers' tiff.
The birds recently returned to their home on Queen Mary's Gardens Lake in Regent's Park, London.
According to a Royal Parks spokesman, wildlife officer Dave Johnson took the female swan to another pond in the gardens, only to later find the swan left behind was trying to find its mate.
Andrew Williams, the gardens' assistant manager, said: "The male and the female tend to mate for life so it was a little unusual that they fell out."
After a trial meeting, the officials decided it was time for the pair to be reunited again.
Mr Williams is happy that the reunion was a success.
He said: "We've had a good release of the swans, with a little bit of a delay looking out onto the water, then we stepped in and I think they look very happy and very glad to be back to their rightful home."
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