The diagnosis of pulmonary diseases using deep learning on chest X-ray images can be affected by the bone structures, the tissue in regions outside the lungs, and the characteristics of the images as burrs, blurring and complex pulmonary structures. To address these issues, a new pulmonary diseases diagnostic framework named BSD is proposed, the innovations of which are: Firstly, three steps of bone suppression, pulmonary parenchyma extraction and pulmonary diseases diagnosis are included. The first two steps can eliminate the influence of bone structures and other tissues. Therefore, better diagnostic results can be obtained based on the extracted boneless pulmonary parenchyma. Secondly, aiming at the characteristics of the chest X-ray image, a new segmentation network named IU-Net is proposed for the pulmonary extraction, in which the original convolution layers of U-Net are replaced by our new designed function modules. Finally, based on the characteristic of boneless pulmonary parenchyma, an enhanced functional module RCA which can better extract the image features is designed, therefore improved the disease diagnosis. In the experiments on the chest X-ray pneumonia datasets, the framework achieved satisfied results in the binary classification with an accuracy and Kappa of 98.73% and 96.80%, respectively. And in the multi-classification task on the COVID-19 radiology database, it achieved an accuracy and Kappa of 95.76% and 95.75%, respectively, which is better than the state-of-the-art. Therefore, BSD framework can better facilitate physicians to diagnose pulmonary disease and increase the diagnostic capabilities.