Skeletal-related events (SRE) are common in patients with bone metastatic lung cancer and have a negative impact on quality of life and survival. The objective of this study is to identify predictive factors for SRE occurrence among this population.We conducted a 3-year retrospective study including 100 lung cancer patients with bone metastasis.Eighty-two patients presented at least one SRE (69.5% at baseline). The median occurrence for SRE was 4.5 months and severe bone pain was the most common SRE (56%). The alkaline phosphatase serum level>120IU/L (hazard ratio [sHR]=2.8; 95% confidence interval (CI) [1.5-5.4]; P=0.002) and calcemia>2.6mmol/L ([sHR]=9.7; 95% CI [5.1-18.4]; P<0.001) were identified as risk factors for SRE occurrence while the presence of an initial SRE was associated with a decrease of this risk ([sHR]=0.2; 95% CI [0.1-0.4]; P<0.001).The elevated alkaline phosphatase serum level and hypercalcemia are risk factors for SRE occurrence in bone metastatic lung cancer patients and should be used as biomarkers to adapt current medical practice for these patients.