Disclosed are a papermaking method comprising the steps of sheet-formation of an aqueous papermaking stock which contains a cellulose fiber or the said fiber and an inorganic filler, dewatering and drying, charaacterized by the addition of a starch ether derivative of a general formula (I): ##STR1## where St--O represents a starch molecule residue, R.sub.1, R.sub.2 and R.sub.3 independently represent an alkyl group having from 1 to 18 carbon atoms or a benzyl group, provided that two or more of these R.sub.1, R.sub.2 and R.sub.3 must not be a benzyl group or an alkyl group having from 5 to 18 carbon atoms at the same time, and any two of these R.sub.1, R.sub.2 and R.sub.3 may be bonded to form a cyclic structure, the said derivative containing the ether bond preferably in a degree of substitution of from 0.01 from 0.1, to the said papermaking stock in an amount of from 0.05 to 5.0% by weight of the cellulose fiber or the total of the said fiber and the inorganic filler in the said stock, as well as the said starch ether derivative of the formula (I) and a method for preparation of the said derivative.