A method for correcting a mask pattern used for dry-etching an object with higher accuracy, and for manufacturing an acceleration sensor and an angular velocity sensor. The object is first etched by a dry-etching process using an uncorrected reference mask pattern. Then, distribution of the size of expansion of a tapered portion formed in a surface of the object is measured. Thereafter, the measured distribution is approximated by using a quadratic curve (Y=AX2+B) so as to determine A and B. Consequently, an amount t of correction for the tapered portion, which is expressed by the following equation (1) and related to a width of an opening of the mask pattern in a position at a distance r from a center of the object to be etched, can be set. In this way, the correction for the tapered portion can be carried out. t=(Ar2+B)/2  (1)