Aiming at the problem of serious distortion of inclination calculation caused by vibration interference of gravity acceleration of drilling tool in MWD, a method of gravity acceleration extraction of drilling tool based on federal adaptive unscented Kalman filter (FAUKF) is proposed. Firstly, a fusion extraction framework of federated gravity information without reset structure is established, and the recursive gravity value based on gyroscope data is selected as the common reference value of federated filtering. The combined gravity acceleration observed by decoupling geomagnetic data is used as sub-filter 1, and the combined gravity acceleration observed by accelerometer data is used as sub-filter 2. Then, the untracked Kalman filter (UKF) algorithm is carried out on the gravity state of the sub-filter. During this period, the vibration resistance of the gravity value observed according to the geomagnetic data is better than that of the accelerometer. The antivibration factor corresponding to the sub-filter 2 is designed. The antimagnetic factor corresponding to the sub-filter 1 is designed to improve the performance of the sub-filter, then the adaptive windowed factor is used to determine the windowed value in the windowed estimation rule and adjust the new information covariance. The real-time estimation of the sub-filter measurement noise covariance is achieved by estimating the new information covariance, and the accuracy of the untracked Kalman filter algorithm is improved. Then reliable local adaptive estimates of gravity information are obtained. Finally, the global estimation of gravity information is obtained by federal information fusion. The results of simulation drilling and real drilling experiments show that the inclination of FAUKF algorithm is reduced by ±1. 9° compared with FKF algorithm, and the inclination of FAUKF algorithm can be controlled within ±1. 2°. This method can effectively extract the gravity acceleration of drilling tools in coal mine, improve the measurement accuracy of inclination, and is an effective method to obtain reliable inclination.