A sensor assembly (600) includes a housing (81) and a circuit board assembly (82). The housing (81) includes a first accommodation cavity (813), a second accommodation cavity (814), a first connection portion (815), a second connection portion (818), and a third accommodation cavity (816). The first connection portion (815) is connected to the first accommodation cavity (813) and one end of the third accommodation cavity (816), and the second connection portion (818) is connected to the second accommodation cavity (814) and the other end of the third accommodation cavity (816). The circuit board assembly is accommodated within the first accommodation cavity, the second accommodation cavity (814), the first connection portion, the second connection portion and the third accommodation cavity. The width of the first connection portion and the second connection portion is less than the width of the first accommodation cavity, the second accommodation cavity and the third accommodation cavity. The first connection portion and the second connection portion are each provided with a buffer groove along the width direction. The sensor assembly may reduce motion artifacts when the user is moving, reduce the influence of the motion artifacts on the monitoring, and improve the accuracy of physiological signal monitoring.
