Cops have arrested another woman in the Robert Kraft prostitution case -- a 58-year-old who allegedly performed a sexual act on the Patriots owner with another woman at the Orchids of Asia Day Spa. 

Jupiter Police arrested Shen Mingbi -- who cops say was in the massage room with Kraft on January 19, 2019. 

According to the police report, Kraft was joined in the massage room by 2 women -- one of whom was Mingbi. 

Officials say the encounter was captured on surveillance and shows both Mingbi and Lei Wang using their hands on Kraft's penis. 

Officials say Mingbi was also involved in sexual acts with several other men at the spa.