The invention provides a children fever monitor and a children fever custody device. The children fever monitor and the children fever custody device comprise the children fever monitor, a mobile phone and the fever custody device operated in the mobile phone. The fever custody system comprises a main control module, a warning module used for warning of children fever spasm, an alarming module for alarming children temperature fever, an inquiring module used for recording of nursing and inquiring of advices of a doctor, and a storage module for detecting data storage and a communication module used for communication connection. The children fever monitor and the children fever custody device can display long-term historic custody data, meanwhile, the conditions of temperature and sweating can be processed in an intelligent mode, the temperature trend can be forecasted, children fever spasm warning is performed on body position variation and microswitch data, and information of medicine taking time and names and dosage of medicine and the like is recorded. In addition, parameter setting of the children fever custody monitor can be achieved, the information can be sent to a server of a hospital information system so that the doctor and a nurse can know the condition of a patient in time and give correct nursing and treating instructions.