The study investigated Denglao Qingguan Decoction (DLQGD), a traditional mixture used for respiratory infections, and its effects against viral pneumonia using network pharmacology and in vitro laboratory tests. 66 active components were identified in the decoction, which can affect 122 targets involved in viral pneumonia. DLQGD showed antiviral activity against RSV, SARS-CoV-2, and H3N2 influenza virus, with an IC50 of 0.4824 mg/mL for RSV, 1.16 mg/mL for SARS-CoV-2, and 1.592 mg/mL for H3N2, with a selectivity index of 15.82, 5.96, and 5.74, respectively. The decoction significantly reduced the viral titer in cell culture supernatants infected with SARS-CoV-2. In Huh-7 cells infected with SARS-CoV-2, DLQGD reduced the mRNA expression of inflammatory mediators IL6, TNF, CXCL8 and CXCL10. It reduced IL6, TNF, IL1B, CXCL8, CXCL10 and CCL5 mRNA expression in RSV-infected HEp-2 cells. DLQGD also decreased the expression of phosphorylated proteins Stat3, Akt and Erk1/2, which is consistent with its anti-inflammatory action. The authors conclude that DLQGD has proven antiviral and anti-inflammatory effects against respiratory viruses in vitro.