A method for isolating trophoblast cells, characterized in that, the method comprises the following steps: step preparing a sample cell suspension from a solution containing cervical exfoliated cells, wherein the cells are suspended in 1x PBS containing 0.2%-0.4% FBS step adding a specific antibody to the sample cell suspension for incubation; a primary antibody is incubated in the following conditions: reacting for 30-90 min at 4°C; and a second antibody-fluorescent labeling complex is incubated in the following conditions: reacting for 20 min at 2°C - 8°C; wherein the specific antibody is an antibody combination specifically recognizing an specific antigen expressed on the surface of or inside of corresponding trophoblast cells, namely, a specific antibody combination is HLA-G+CK7, HLA-G+CK18, HLA-G+β-HCG, CD31+HPL, MMP9+CD31, HLA-G+HPL, HLA-G+MMP9, HLA-G+CD31, HLA-G+P, CD31+P, HLA-G+CDH5, CD31+CDH5, CD31+CK7+HLA-G, HLA-G+CK18+CD31, HLA-G+β-HCG+CD31, CD31+HPL+HLA-G, MMP9+CD31+HLA-G, CD31+P+HLA-G or HLA-G+CDH5+CD31; and step performing fluorescence labeling and microfluidics cell sorting of a cell resuspension incubated in the step by a microfluidic cell sorting chip to obtain isolated and purified placental trophoblast cells; wherein a liquid-phase cell sorting system is 0.2% - 0.4% Triton-X-100; the microfluidic cell sorting chip comprises a substrate and a cover plate fitted therewith; wherein one side of the substrate is provided with a main channel, a side channel A and a side channel B, and the two side channels are respectively close to left and right end portions of the main channel; and wherein another side of the substrate is provided with an inlet C, an inlet S, an outlet N and an outlet T; all the two inlets and the two outlets penetrate the substrate to communicate with the channels on the other side; and a position of the inlet C corresponds to the left end portion of the main channel; a position of the inlet S corresponds to the end portion of the side channel A; a position of the outlet N corresponds to the right end portion of the main channel; and a position of the outlet T corresponds to the end portion of the side channel B; and a deflection electrode device is further disposed in the main channel and at a convergence site of the outlet N and the outlet T; and each of the main channel, the side channel A and the side channel B has a width not greater than 1000 μm and a depth not greater than 500 μm. step preparing a sample cell suspension from a solution containing cervical exfoliated cells, wherein the cells are suspended in 1x PBS containing 0.2%-0.4% FBS step adding a specific antibody to the sample cell suspension for incubation; a primary antibody is incubated in the following conditions: reacting for 30-90 min at 4°C; and a second antibody-fluorescent labeling complex is incubated in the following conditions: reacting for 20 min at 2°C - 8°C; wherein the specific antibody is an antibody combination specifically recognizing an specific antigen expressed on the surface of or inside of corresponding trophoblast cells, namely, a specific antibody combination is HLA-G+CK7, HLA-G+CK18, HLA-G+β-HCG, CD31+HPL, MMP9+CD31, HLA-G+HPL, HLA-G+MMP9, HLA-G+CD31, HLA-G+P, CD31+P, HLA-G+CDH5, CD31+CDH5, CD31+CK7+HLA-G, HLA-G+CK18+CD31, HLA-G+β-HCG+CD31, CD31+HPL+HLA-G, MMP9+CD31+HLA-G, CD31+P+HLA-G or HLA-G+CDH5+CD31; and step performing fluorescence labeling and microfluidics cell sorting of a cell resuspension incubated in the step by a microfluidic cell sorting chip to obtain isolated and purified placental trophoblast cells; wherein a liquid-phase cell sorting system is 0.2% - 0.4% Triton-X-100; the microfluidic cell sorting chip comprises a substrate and a cover plate fitted therewith; wherein one side of the substrate is provided with a main channel, a side channel A and a side channel B, and the two side channels are respectively close to left and right end portions of the main channel; and wherein another side of the substrate is provided with an inlet C, an inlet S, an outlet N and an outlet T; all the two inlets and the two outlets penetrate the substrate to communicate with the channels on the other side; and a position of the inlet C corresponds to the left end portion of the main channel; a position of the inlet S corresponds to the end portion of the side channel A; a position of the outlet N corresponds to the right end portion of the main channel; and a position of the outlet T corresponds to the end portion of the side channel B; and a deflection electrode device is further disposed in the main channel and at a convergence site of the outlet N and the outlet T; and each of the main channel, the side channel A and the side channel B has a width not greater than 1000 μm and a depth not greater than 500 μm.