Considering problems that there are different urgency levels of health data and limited resources of nanonodes, an energy-balanced routing protocol based on data priority (DPER) is proposed. The priority of data and the lung terahertz time-varying channel characteristics are considered in this protocol creatively. The link selection function proposed in this paper can achieve the goal of allocating different data transmission rates for different priorities of data. The simulation results prove that the DPER protocol can provide different average delays for data with different priorities, and the degree of differentiation of data with different priorities is higher. In addition, the DPER protocol also has greater advantages in terms of packet transmission success rate and average throughput.