Spectral feature selection, an excellent dimensionality reduction method, is extensively used in knowledge mining and protein sequence analysis. However, the graph representation derived from data with potential noises significantly impacts feature selection performance. Similarly, its performance deteriorates when label information is ignored, as the selected features have poor discrimination ability. To overcome these drawbacks, this article optimizes neighborhood structure and further constructs the conditional entropy based on neighborhood purity to generate a precise graph representation incorporating label information to enhance the compactness of intra-class samples and increase the dispersion between inter-class samples. Then this article proposes a novel spectral feature selection method. Specifically, the method dynamically learns the precise graph representation from low-dimension space, which can effectively preserve the local structure of data, and the global structure is preserved by introducing a constraint term that maintains the graph representation before and after dimension reduction. Additionally, ℓ2,1-norm is introduced to ensure row sparsity and select the valuable features. The alternative optimization algorithm is employed to solve the optimization problem and its convergence is theoretically analyzed. Finally, to assess the performance of the proposed method, a series of comprehensive experiments are performed on several real-world datasets.