To solve the attitude control problem of small quadrotor according to its complex coupling, non-linear and serious internal/external disturbance feature, a control scheme based on active disturbance rejection control technique is proposed. The dynamic model is established with Newton-Euler formalism, and the uncertainty, coupling and parameter perturbation are considered as total disturbance. Extended State Observer is used to estimate and compensate the total disturbance, the Non-linear State Error Feedback is used to restrain the compensate error, a model for simulation is established. The result of the simulation shows that the Extended State Observer of the Active Disturbance Rejection Control technique can estimate/compensate disturbance well under circumstance of parameter perturbation and disturbance. Attitude controller based on Active Disturbance Rejection Control theory shows good dynamic quality, steady-state accuracy and strong robustness.