The invention relates to an acid-soluble pressure-bearing plugging agent for drilling fluid and a preparation method. The acid-soluble pressure-bearing plugging agent contains a friction material, a bridging material, a filler material, iron tailing sand, volcanic ash powder, woody activated carbon powder, nano calcium-zinc phosphate, paraffin, polyalcohol fatty acid ester, titanium white, red clay, alginic acid, dimethyl diallyl ammonium chloride, polyvinyl acetate, glyceryl monostearate, a glued stone cementing material, copper oxide, Dibenzyl disulfide, alpha-n-octyl-cyanoacrylate, sodium caseinate, steel slag, white carbon black, dolomite powder, manganese dioxide, diatomite, dibutyl phthalate, polyvinyl alcohol, tert-butylhydroquinone, phthalic anhydride and H2O. According to the acid-soluble pressure-bearing plugging agent for the drilling fluid and the preparation method, by using the preparation method, the defects in the prior art that on-site operating methods are tedious, operating requirements are strict, plugging performance is often poor due to invasion of surrounding solid-state particulate matters, a plugging framework is damaged, and a motor shaft or rotating shaft is subjected to expanding and contracting under the action of stress of the shaft during rotating due to infirm connection are avoided.