Glen Evans was left with a broken nose and his bride Georgina was punched by an unknown person at Fanhams Hall Hotel in Hertfordshire on 10 August 2014.
Lee Doyle, 37, of Houghton Regis and Gary Hutson, 46, of Luton, both guests at another wedding, denied hitting Mr Evans.
They were found guilty by a jury.
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During the trial, St Albans Crown Court heard an argument had broken out when Doyle and Hutson asked Mr and Mrs Evans and their friends to move away from a fireplace.
The newly married couple and their group were having drinks at the hotel following their own reception at another venue.
Mr Evans said Doyle, Hutson and the other groom confronted him, claiming the area was reserved for them, although the Evans wedding party had been put there by bar staff.
He said the two men hit him, and he was kicked and punched by others who joined in the attack. Mrs Evans was then also punched, leaving her bruised.
She told the court: "I went on honeymoon with my husband having a broken nose and me with bruising to my face,"
Doyle denied punching Mr Evans but admitted "grappling" with him on the floor.
He described Mr Evans as "irate and aggressive" and claimed he and Hutson wanted to "calm the situation down".
Both Doyle and Hutson were found guilty of affray and will be sentenced on 18 March.
Two men accused of starting a brawl in which a bride and groom were punched when two wedding parties clashed, have been convicted of affray.