Background/aim: Determining the severity of systemic sclerosis related interstitial lung disease (SSc-ILD) is based on clinical and radiological findings, inflammation marker levels, and carbon monoxide diffusing capacity of the lung (DLCO). Recently studies are ongoing for objective and easy markers. Neutrophil/lymphocyte ratio (NLR) is shown to be a good marker for inflammation in recent clinical trials. In this study, we aimed to identify the possible relationship between NLR and carbon monoxide transfer coefficient (KCO) of SSc-ILD patients. Materials and methods: Fifty-nine patients with systemic sclerosis (SSc) were enrolled in the study. We used high-resolution computed tomography for diagnosis and used DLCO to evaluate degree of lung involvement. Complete blood cell counts and acute phase reactants were included as laboratory assessments. Results: NLR values were significantly higher in the SSc-ILD group (3.66 ± 1.32 vs. 2.85 ± 1.12, P = 0.01) and correlated negatively with KCO. The NLR cut-off value was 3.21, its sensitivity was 81%, and its specificity was 81%. Conclusion: NLR level may serve as a marker of lung involvement in the presence of ILD in patients with SSc.