The invention discloses a preparation method of water-retention non-woven fabric. The preparation method of the water-retention non-woven fabric includes the followings steps that S1, a non-woven fabric inner layer and a non-woven fabric surface layer are prepared; S2, a hydrophobic treatment solution of hydrophilic fibers is prepared; S3, local esterification and hydrophobic treatment are conducted on the non-woven fabric surface layer to make the non-woven fabric surface layer have continuous hydrophobic stripes or continuous hydrophobic grids; S4, the non-woven fabric inner layer and the non-woven fabric surface layer are combined, and secondary spunlace is conducted to obtain the water-retention non-woven fabric. By adopting full-cotton non-woven fabric as a raw material, by conductingthe local esterification and grafted nanometer silicon dioxide on the full-cotton non-woven fabric, the continuous hydrophobic stripes or the continuous hydrophobic grids are formed on the non-wovenfabric surface layer, the obstruction effect of the hydrophobic stripes or the hydrophobic grids on water flow is adopted, the pathway that moisture directly falls through the surface layer is obstructed, and therefore the falling speed of the moisture is reduced. The invention further discloses the water-retention non-woven fabric and a preparation method of a mask.