A sound and vibration information collecting mechanism which collects low-frequency sound and vibration information with a predetermined frequency or lower from a detection target, the mechanism comprising: a resonance layer which includes a natural oscillator having a natural frequency within a frequency band of the sound and vibration information being a collection target, and generates a resonance carrier by the natural oscillator emphasizing the sound and vibration information; and a sensor which detects the resonance carrier, wherein the detection target is a living body, and the sound and vibration information is a biosignal, the biosignal is sound and vibration information of a cardio-vascular system, and the natural frequency of the natural oscillator is within a frequency band including a frequency of first heart sound or second heart sound included in the sound and vibration information of the cardio-vascular system, wherein a first layer which is disposed on the back side of the trunk of the living body and to which the sound and vibration information of the cardio-vascular system propagates; a second layer which includes: a casing for resonance having an arrangement space formed as a hole portion or a groove portion where to arrange the natural oscillator and the sensor; and a film covering the arrangement space, and which functions as the resonance layer; and a third layer which is disposed opposite to the first layer across the second layer to damp the externally inputted sound and vibration and is provided integrally, wherein the third layer has a property of damping sound and vibration with a frequency not corresponding to the natural frequency of the natural oscillator, wherein the first layer, the natural oscillator of the second layer and the third layer are each formed of a three-dimensional knitted fabric, wherein a spring constant of the first layer and a spring constant of the natural oscillator of the second layer approximate a spring constant of muscle of a human body, and wherein a spring constant of the third layer is higher than the spring constants of the first layer and the natural oscillator of the second layer. a resonance layer which includes a natural oscillator having a natural frequency within a frequency band of the sound and vibration information being a collection target, and generates a resonance carrier by the natural oscillator emphasizing the sound and vibration information; and a sensor which detects the resonance carrier, wherein the detection target is a living body, and the sound and vibration information is a biosignal, the biosignal is sound and vibration information of a cardio-vascular system, and the natural frequency of the natural oscillator is within a frequency band including a frequency of first heart sound or second heart sound included in the sound and vibration information of the cardio-vascular system, wherein a first layer which is disposed on the back side of the trunk of the living body and to which the sound and vibration information of the cardio-vascular system propagates; a second layer which includes: a casing for resonance having an arrangement space formed as a hole portion or a groove portion where to arrange the natural oscillator and the sensor; and a film covering the arrangement space, and which functions as the resonance layer; and a third layer which is disposed opposite to the first layer across the second layer to damp the externally inputted sound and vibration and is provided integrally, wherein the third layer has a property of damping sound and vibration with a frequency not corresponding to the natural frequency of the natural oscillator, wherein the first layer, the natural oscillator of the second layer and the third layer are each formed of a three-dimensional knitted fabric, wherein a spring constant of the first layer and a spring constant of the natural oscillator of the second layer approximate a spring constant of muscle of a human body, and wherein a spring constant of the third layer is higher than the spring constants of the first layer and the natural oscillator of the second layer.