The invention discloses a triazine weedicide, and metabolite molecular engram polymer microspheres, a preparation method and an application thereof, which relate to molecular engram polymer microspheres and a preparation method and an application thereof and are used for solving the problem that the conventional molecular engram polymer can only specially absorb one kind of substance and realizing the effect of separating and enriching a plurality of triazine pesticide residues in a sample respectively. The molecular engram polymer microspheres are prepared by the following steps of: dissolving double template molecules and methacrylic acid into acetonitrile; oscillating; adding trimethylolpropane trimethylacrylate and azobisisobutyronitrile; performing ultrasonic treatment, charging nitrogen, removing oxygen and sealing; and heating in a constant-temperature water bath, cooling, grinding, sieving, eluting and drying. The molecular engram polymer microspheres are applied to a filling material of a solid phase extraction column. A product obtained in the invention has the advantages of high specificity, large absorption amount, wide application range, simple method and low cost. High specific separating and enriching characteristics on the triazine weedicide are achieved, the recovery rate is 65-110 percent, and the requirement of multiple residues can be met.