A medical system, comprising: a medical terminal device including an operation display unit adapted to display an operation screen used to operate a medical care device, operator identification means adapted to identify an operator to perform medical care, patient identification means adapted to identify a patient to receive the medical care, and device identification means adapted to identify a medical care device to be used for the medical care; a plurality of medical care devices; information storage means adapted to store device information on the plurality of medical care devices, operator information on a plurality of operators, and patient information on a plurality of patients; and control means adapted to, based on the operator information corresponding to the operator identified by the operator identification means, the patient information corresponding to the patient identified by the patient identification means, and the device information corresponding to the medical care device identified by the device identification means, display an operation screen on the medical care device to be used for the medical care as an operation screen which reflects a setting made by the operator to perform the medical care and a setting made by the patient to receive the medical care, the operation screen being displayed on the operation display unit, characterized in that the plurality of medical care devices each include terminal device attachment means to which the medical terminal device is attached, and a controller sensor adapted to detect attachment of the medical terminal device, the medical care device includes device-side operation means used to operate the device and device-side control means adapted to control the device; and when the medical terminal device is attached to the terminal device attachment means and the controller sensor detects the attachment of the medical terminal device, the device-side control means is adapted to stop a function of the device-side operation means. a medical terminal device including an operation display unit adapted to display an operation screen used to operate a medical care device, operator identification means adapted to identify an operator to perform medical care, patient identification means adapted to identify a patient to receive the medical care, and device identification means adapted to identify a medical care device to be used for the medical care; an operation display unit adapted to display an operation screen used to operate a medical care device, operator identification means adapted to identify an operator to perform medical care, patient identification means adapted to identify a patient to receive the medical care, and device identification means adapted to identify a medical care device to be used for the medical care; a plurality of medical care devices; information storage means adapted to store device information on the plurality of medical care devices, operator information on a plurality of operators, and patient information on a plurality of patients; and control means adapted to, based on the operator information corresponding to the operator identified by the operator identification means, the patient information corresponding to the patient identified by the patient identification means, and the device information corresponding to the medical care device identified by the device identification means, display an operation screen on the medical care device to be used for the medical care as an operation screen which reflects a setting made by the operator to perform the medical care and a setting made by the patient to receive the medical care, the operation screen being displayed on the operation display unit, characterized in that the plurality of medical care devices each include terminal device attachment means to which the medical terminal device is attached, and a controller sensor adapted to detect attachment of the medical terminal device, the medical care device includes device-side operation means used to operate the device and device-side control means adapted to control the device; and when the medical terminal device is attached to the terminal device attachment means and the controller sensor detects the attachment of the medical terminal device, the device-side control means is adapted to stop a function of the device-side operation means.