Malaysian news agency Bernama reported that the police raid, which took place Tuesday night in Puchong, also saw two Malaysian men, believed to be customers, arrested.
The report cited investigators as saying the reflexology center, which was found to be operating without a valid license, would screen customers before they were allowed to enter in order to avoid detection by local authorities.
Customers were charged around RM160 ($38) for sex services, an officer said, adding that the two men and seven Vietnamese women were taken to the Serdang district police headquarters for further investigation.
Several Vietnamese women have been caught in recent raids by Malaysian authorities on entertainment centers, massage parlors and night clubs.
Last week, 11 Vietnamese were among 20 foreign women detained as Malaysian immigration officers raided a Penang entertainment center. Earlier this month, Malaysian authorities captured 184 foreign women, including four Vietnamese, for allegedly working illegally and offering sexual services in Kuala Lumpur.
In recent years, Vietnamese workers, mainly women, have visited neighboring countries like Thailand, Singapore and Malaysia and stayed on to work illegally.
Many have been caught, detained and deported.