A physical quantity detection apparatus includes a signal output section, a correction value calculation section, and a processing section. The signal output section outputs signals in accordance with a change in physical quantity of a detected object. The correction value calculation section calculates a correction value. The processing section corrects values based on actual output values of the signal output section with the correction value, calculates physical quantities of the detected object based on corrected values, and outputs calculated physical quantities. The correction value calculation section calculates the correction value based on primary error amounts that are differences between post-interpolation actual output values calculated by executing a linear function interpolation process to the values based on the actual output values within a predetermined physical quantity range and the values based on the actual output values corresponding to the post-interpolation actual output values.