The bus park in Kiambu Town will be moved elsewhere following a directive by the Environment and Lands Court.
Postal Corporation and Fave Oil Ltd sued the county government for invading the Sh100 million plot belonging to the parastatal and converting it into a matatu terminus.
The corporation signed a 10-year lease with Fave Oil, which is owned by Mr James Mungai.
At the time of the invasion, the businessman was putting up a petrol station at the piece after getting approval even from the devolved government.
The land is next to Kiambu Post Office and Mr Mungai's lease was to take effect on November 2017.
However, Governor Ferdinand Waititu reportedly ordered the demolition of structures and felling of trees on the plot on October 3, 2017.
After that, the county government directed that public service vehicles use the land.
Traders also put up stalls and kiosks on the contested plot.
Postmaster-General Dan Kagwe wrote to Cabinet secretaries Mwangi Kiunjuri (Devolution) and Joe Mucheru (ICT) and Inspector-General of Police Joseph Boinnet seeking their intervention but his efforts yielded little.
The parastatal and Mr Mungai then filed a case in court.
The Lands court ordered the county government to stop the invasion of the land but the directive was not obeyed.
The court, which sits in Thika, has issued another order, directing the devolved government to evict matatu operators from the plot until the case is heard and determined.
"The defendant is directed to remove the bus stage on the suit property," the court said.
Mr Joel Mageto, who is managing the property on behalf of the corporation, told the court that the parastatal has a certificate of lease for 99 years.
He said the lease period began on April 1, 1977, adding that the parastatal signed a lease agreement with Mr Mungai's company.
However, Kiambu County Secretary Martin Njogu attempted to exonerate his employer, saying it is matatu operators who should be sued "since they are the ones who invaded the land as it had become a criminals' den".
While giving the directive, the court said the county government did not dispute the fact that the plot belongs to the corporation.
"There is no doubt that the property has been invaded and turned into a terminus by matatu operators with the blessings of the defendant," the court said.
"It is evident, therefore, that the property is in danger of being damaged or wasted before the suit is heard and determined."
It added that even if the corporation had neglected the land, that did not give the county a reason to invade it.