Abstract: The present invention discloses temporary plugging agent for drilling fluid and preparation method thereof, and water-based drilling fluid and use thereof. The temporary plugging agent for drilling fluid is obtained by controlling gelatinized starch and a vinyl grafted monomer to have a polymerization reaction in an activator solution in the presence of a cross-linking agent and an initiator; the vinyl grafted monomer comprises acrylic acid, acrylamide, and 2-acrylamide-2-methyl propanesulfonic acid; the gelatinized starch is obtained by adding starch into deionized water to have a gelatinization reaction.

Abstract: The present invention relates to the technical field of petroleum drilling, specifically provides an encapsulating agent and preparing method thereof, and a drilling fluid, wherein the encapsulating agent comprises an acrylamide monomer structure unit represented by formula (I), an anti-temperature monomer structure unit represented by formula (II) and an cation monomer structure unit represented by formula (III); wherein R1 and R2 are each independently H, and linear or branched alkyl of C1-C15, and R3 is H or the linear or branched alkyl of C1-C5. The drilling fluid provided in the present invention has strong inhibition property and stable rheological property.