According to a report in The National Business section, the other five were not named. Homelink has branches across most Chinese cities, and helps wealthy Chinese to make property investments overseas.
The ban will last one month starting today, and will be reviewed after that, the China banking regulatory commission said.
The regulator says it found some commercial banks had illegally transferred money from mortgage loan accounts to third parties, who were not involved in the properties for which the mortgages were taken out. These third parties were found to have further moved the money to one of six real estate companies in Shanghai, according to the Shanghai government.
Some of the estate agencies also helped home buyers to acquire down-payments for property purchases through illegal channels, it says.
The banking regulator has also asked seven Shanghai banks to stop giving housing loans to individuals for two months after they were found to have broken rules in making cash advances.
The ban will have a major impact on the property sector at home and will affect overseas sales because the real estate agencies involved account for the majority of homes available to Chinese buyers.
A Chinese news portal, thepaper.com, quotes a HomelinkLink official as saying the firm will have to adopt alternative measures but he did not elaborate.