PROBLEM TO BE SOLVED: To provide a magnetic field measuring apparatus and magnetic field measuring method capable of measuring a weak magnetic field from a living body and being downsized.SOLUTION: A magnetic field measuring apparatus and magnetic field measuring method according to the present invention: measure a magnetic field from an object 99 by a magnetic sensor group 11 including a plurality of magnetic sensors 1； and calculates a common noise component applied to an observation amount 11 of the magnetic sensors 1 of all channels included in the magnetic sensor groups 11 as an estimate value of the magnetic noise component from the outside. The magnetic field from the object 99 is detected by subtracting an average value thereof from the observation amount of each of the magnetic sensors 1.SELECTED DRAWING: Figure 1【課題】生体からの微弱な磁場を測定でき、且つ小型化できる磁場測定装置及び磁場測定方法を提供すること。【解決手段】本発明の磁場測定装置及び磁場測定方法では、複数の磁気センサ１を含む磁気センサ群１１で対象物９９からの磁場を測定し、磁気センサ群１１に含まれる全チャンネルの磁気センサ１の観測量１１に加わる共通ノイズ成分を、外部からの磁気ノイズ成分の推定値として算出する。そして、その平均値を各々の磁気センサ１の観測量から減ずることで対象物９９からの磁場を検出する。【選択図】図１
