An acceleration sensor (SE) comprising: a substrate (ML); a fixing portion (FU) formed on the substrate; a mass body (MS) that includes a first portion (HVU) provided on one side of the fixing portion (FU) and a second portion (LTU) provided on the other side of the fixing portion (FU), is formed on the substrate (ML), and is displaceable in a thickness direction of the substrate(ML); a beam (BM) that is formed on the substrate (ML) and connects the fixing portion (FU) and the mass body (MS) to each other; a first fixed electrode (FEL1) disposed at a position facing the first portion; and a second fixed electrode (FEL2) disposed at a position facing the second portion, wherein a first surface (SUR1) of the substrate is a surface facing the first fixed electrode (FEL1) and the second fixed electrode (FEL2), wherein a second surface (SUR2) of the substrate is a surface opposite to the first surface, wherein a value obtained by multiplying a distance (L1) between a first center of gravity (CG1) of the first portion and a center of the fixing portion (FU) by a mass of the first portion is greater than a value obtained by multiplying a distance (L2) between a second center of gravity (CG2) of the second portion and a center of the fixing portion (FU) by a mass of the second portion, wherein a first number of first opening portions (OP1) are formed in a region corresponding to the first portion of the mass body, on the first surface (SUR1) of the substrate (ML), wherein a second number of second opening portions (OP2) are formed in a region corresponding to the first portion of the mass body, on the second surface (SUR2) of the substrate (ML), wherein the first opening portion (OP1) and the second opening portion (OP2) are connected to each other to form a plurality of first through portions in the substrate, and wherein the first number is greater than the second number. a substrate (ML); a fixing portion (FU) formed on the substrate; a mass body (MS) that includes a first portion (HVU) provided on one side of the fixing portion (FU) and a second portion (LTU) provided on the other side of the fixing portion (FU), is formed on the substrate (ML), and is displaceable in a thickness direction of the substrate(ML); a beam (BM) that is formed on the substrate (ML) and connects the fixing portion (FU) and the mass body (MS) to each other; a first fixed electrode (FEL1) disposed at a position facing the first portion; and a second fixed electrode (FEL2) disposed at a position facing the second portion, wherein a first surface (SUR1) of the substrate is a surface facing the first fixed electrode (FEL1) and the second fixed electrode (FEL2), wherein a second surface (SUR2) of the substrate is a surface opposite to the first surface, wherein a value obtained by multiplying a distance (L1) between a first center of gravity (CG1) of the first portion and a center of the fixing portion (FU) by a mass of the first portion is greater than a value obtained by multiplying a distance (L2) between a second center of gravity (CG2) of the second portion and a center of the fixing portion (FU) by a mass of the second portion, wherein a first number of first opening portions (OP1) are formed in a region corresponding to the first portion of the mass body, on the first surface (SUR1) of the substrate (ML), wherein a second number of second opening portions (OP2) are formed in a region corresponding to the first portion of the mass body, on the second surface (SUR2) of the substrate (ML), wherein the first opening portion (OP1) and the second opening portion (OP2) are connected to each other to form a plurality of first through portions in the substrate, and wherein the first number is greater than the second number. <EOS>