Interstitial lung disease (ILD) is an umbrella term representing a heterogeneous group of restrictive lung disorders with destructive abnormalities in the lung interstitium. The overlapping clinical onset of various ILD subtypes poses significant challenges in diagnosis and management of the disease. Various omics technologies have explored disease-specific molecular markers, crucial for understanding the complex pathophysiology underlying disease progression. Proteomics, a rapidly advancing high-throughput omics tool, captures dynamic protein changes within a biological system, depicting its actual functional state. This enables comprehensive proteome profiling, facilitating the identification of specific biomarkers and pathways, thereby enhancing diagnostic precision and paving the way for targeted therapeutic interventions. This review highlights recent proteomic discoveries in idiopathic pulmonary fibrosis, autoimmune ILDs, exposure-related ILDs, and sarcoidosis, including emerging therapeutic avenues. It summarizes dysregulated pathways and potential biomarkers crucial for differential diagnosis, prognosis, disease progression, and treatment responses. The pathogenesis of ILD involves complex interactions of complement activation, humoral immune responses, and extracellular matrix organization pathways, and the expression levels of these pathway mediators vary across ILD stages and subtypes. Further validation of these pathways and their mediators through multicentric, large-cohort studies across diverse geographical locations is needed to enhance disease understanding and develop ”true” clinical biomarkers.