Head pose and facial feature detection are important for face analysis. However, many studies reported good results in constrained environment, the performance could be decreased due to the high variations in facial appearance, poses, illumination, occlusion, expression and make-up. In this paper, we propose a hierarchical regression approach, Dirichlet-tree enhanced random forests (D-RF) for face analysis in unconstrained environment. D-RF introduces Dirichlet-tree probabilistic model into regression RF framework in the hierarchical way to achieve the e±ciency and robustness. To eliminate noise in°uence of unconstrained environment, facial patches extracted from face area are classi¯ed as positive or negative facial patches, only positive facial patches are used for face analysis. The proposed hierarchical D-RF works in two iterative procedures. First, coarse head pose is estimated to constrain the facial features detection, then the head pose is updated based on the estimated facial features. Second, the facial feature localization is re¯ned based on the updated head pose. In order to further improve the e±ciency and robustness, multiple probabilitic models are learned in leaves of the D-RF, i.e. the patch's classi¯cation, the head pose probabilities, the locations of facial points and face deformation models (FDM). Moreover, our algorithm takes a composite weight voting method, where each patch extracted from the image can directly cast a vote for the head pose or each of the facial features. Extensive experiments have been done with di®erent publicly available databases. The experimental results demonstrate that the proposed approach is robust and e±cient for head pose and facial feature detection.