Introduction The majority of cancer morbidity and mortality is caused by metastatic events, where metastasis accounts for 90% of the mortality rate. The most common predilection of metastatic spine disease was thoracic (70%), lumbar (20%), and cervical (10%). One of the markers in cancer is pro-inflammatory cytokines and chemokines that present around the tumor environment. Several studies showed a strong correlation between neutrophil/lymphocytes ratio (NLR), platelet/lymphocytes ratio (PLR), and lymphocytes/monocytes ratio (LMR) and prognostic of the tumor. Methods This consecutive retrospective study was carried out from January 2014 to December 2019. Patient eligibility criteria were as follows: 1) metastatic spine disease patient; 2) history of cancer. The patients with 1) history of trauma; 2) metastatic spine disease with infection; 3) history of tuberculous spondylitis were excluded from the study. The outcome of this study is to assess the eligibility of LMR in predicting the survival rate of metastatic spine disease and to look for the cut-off value of the LMR. Results The ROC analysis was carried out between the LMR and the survival time of the patients. The sensitivity and specificity of the LMR was 0.857 and 0.879, respectively. The Youden index was performed to obtain the LMR cut-off value shown in Figure 2. The cut-off value of the LMR was 2.5250. Hence, the LMR ratio of more than 2.5250 was classified into a high LMR and vice versa. Conclusions In this study, the cut-off value for serum levels of the LMR was 2,5250 with a sensitivity value of 85,7% and specificity of 87,9%. There is a significant association between LMR and survival rate as a prognostic marker for spinal metastases.