In order to solve the problem that the trajectory tracking control of small unmanned helicopters is affected by internal and external disturbances such as the accuracy of system mathematical model, the attitude measurement error caused by the low-cost MEMS and the interference of flight environment, a linear/ nonlinear hybrid active disturbance rejection control (ADRC-LADRC) method was designed for the unmanned helicopter trajectory tracking controller. Furthermore, a controller parameter tuning method based on bacterial foraging optimization-flower pollination algorithm (BFO-FPA) was proposed, which improved the convergence speed of BFO algorithm and enhanced the global search capability of FPA algorithm. Finally, with the ALIGN unmanned helicopter′s tail-locking spiral climb flight test, it was verified that the optimized active-disturbance rejection trajectory tracking controller based on BFO-FPA algorithm can effectively overcome the influence of internal and external disturbances on the unmanned helicopter and improve the trajectory tracking accuracy and robustness of controller.