Measuring the heartbeat and respiration of small conscious animals is important for assessing their health and behavior, but present techniques such as electrocardiogram (ECG), ultrasound, and auscultation rely on close skin contact with the animal. These methods can also require surface preparation, cause discomfort or stress to animals, and even require anesthetic administration, especially for birds, reptiles, and fish. Here, we show that radio frequency near-field coherent sensing (NCS) can provide a new solution to animal vital sign monitoring while ensuring minimal pain and distress. We first benchmarked NCS with synchronous ECG on an anesthetized rat. NCS was then applied to monitor a conscious hamster from outside its cage, and was further extended to a parakeet, Russian tortoise, and betta fish in a noninvasive manner. Our system can revolutionize vital sign monitoring of small conscious animals in their laboratory living quarters or natural habitats.