Mr. Moi transferred to himself 53 acres of land belonging to widow Susan Cheburet Chelugui, the judge ruled.
The land was illegally seized 36 years ago but only transferred to Mr. Moi's name in 2007.
The former president, who remains Kenya's longest-serving leader, was accused by Ms. Chelugui and her son David Chelugui of transferring their family land into his name two years after Ms. Chelugui's husband passed away.
Mr. Moi is then said to have sold the land to Rai Plywood Limited, a timber firm, the BBC reports.
Rai Plywood Limited told the judge that it had bought the land from Moi in 2007 after thorough legal checks.
According to report garnered by newsmen, Mr. Moi was unable to provide the court any proof of how he came to possess the land.
Judge Anthony Ombwayo said Mr. Moi had behaved in a way that was "unconstitutional, irregular, unprocedural" and "tainted".
Mr. Moi became Kenya's second president in 1978 and served until 2002.
He ruled the country with an iron fist and was accused of human rights abuses.
Under international pressure, he allowed multi-party elections in 1992, which were marred by widespread violence and allegations of rigging. SHARE THIS NEWS USING ANY OF THE BUTTON BELOW PLACE YOUR TEXT ADVERT BELOW ⬇⬇⬇