The invention discloses placental villus plate mesenchymal stem cells. An extraction method of the placental villus plate mesenchymal stem cells includes the following steps that 1, a placental villus plate is obtained; 2, blood vessels and villus tissue are removed; 3, the villus plate is cleaned till the blood color disappears; 4, the villus plate is sheared into 0.5-5 mm<2> tissue microblocks, and the tissue microblocks are cleaned; 5, tissue digestive juice containing pancreatin, collagenase II, collagenase IV and hyaluronidase is added for digestion; 6, filtration and centrifugation are carried out; 7, culture is carried out; 8, cell digestion is carried out with 0.25% pancreatin when the cell confluence reaches 70-90%; 9, subculturing is carried out; 10, detection is carried out; 11, cryopreservation is carried out; 12, database building is carried out. According to the method, the steps are simple, and a large number of mesenchymal stem cells can be rapidly obtained from the placental tissue; the separation process does not need too much cleaning operation; the use of antibiotics is omitted, so that the purity of the placental villus plate mesenchymal stem cells obtained after separation is high.