The charge related to a credit invoice for US$589,890 (£297,025), which the prosecution said was used to falsely exaggerate Baugur's accounts in 2001, when it was still a public company.
There were 40 charges brought against the Baugur founder and chief executive during a five-year legal battle. He was acquitted of 39 of these. A company spokesman said Baugur completely supports Jóhannesson and maintains his innocence.
Jóhannesson's defence team is understood to be preparing to make an appeal to the Supreme Court.
The initial complaint came from US wholesaling group Nordica, who brought charges against Baugur, Jóhannesson and five co-defendants.
The criminal investigation was then instigated by the Icelandic government and, as prosecutors, they will have to cover 90 per cent of the trial costs.