Abstract Early diagnosis based on precise monitoring of the vital organs in real‐time can provide the opportunity for subsequent curative treatments and medical decisions. Here, it is reported that the instantaneous monitoring of physiological responses in contractile living organs such as the heart, lung, and urinary bladder using a vertical graphene strain sensor (VGS), which possesses remarkable sensitivity and stability. The electrical resistance of VGS (i.e., sensitivity) corresponding to the minute contractile motion of living organs is monitored, which displacement in organs is less than a few mm in scale. For pathological diagnosis, it is compared normal and damage rodent models, including models of myocardial infarction, pulmonary fibrosis, and spinal cord injury, highlighting the capability of the VGS sensor to discern symptoms and guide medical decisions based on the lesions. The results suggest that the VGS could be useful in implantable biocompatible applications and may be a promising component of in vivo diagnostic platforms.