The invention discloses an energy optimization navigation unit based on combined navigation, which comprises a navigation module, a computation module, a control module and a display module. The navigation module, the computation module and the display module are connected with the control module, and the navigation module is further connected with the computation module. The energy optimization navigation unit is a handheld energy optimization GNSS (global navigation satellite system) receiver based on an inertial navigation device, and the handheld energy optimization GNSS receiver integrates advantages, including high precision, low power consumption, high independency and external interference resistance, of the inertial navigation device and a common GNSS receiver. On the premise of guaranteeing the navigation precision and sensitivity, the power consumption can be reduced to be 21% of the original power consumption. In addition, compared with the pure inertial navigation device, the energy optimization navigation unit can effectively control accumulated errors on the premise of keeping low power consumption and low dependency on external environments.