Background:Inflammation　and　cancer　are　closely　related　to　each　other.　As　a　parameter　that　can　reflect　inflammation　and　host　immune　reaction,　elevated　blood　neutrophil　to　lymphocyte　ratio　(NLR)　has　been　confirmed　to　be　correlated　with　poor　prognosis　in　a　variety　of　cancers.　However,　this　remains　controversial　in　breast　cancer.　Thus,　we　performed　this　updated　meta-analysis　to　further　clarify　whether　high　NLR　could　be　a　predictor　of　survival　in　breast　cancer　patients.Methods:We　searched　on　PubMed　Database　and　Cochrane　Library.　Overall　survival　(OS),　disease-free　survival　(DFS),　and　cancer-specific　survival　were　used　as　outcome　events,　and　hazard　ratio　(HR)　was　chosen　as　the　parameter　to　evaluate　the　correlation.Result:Eighteen　eligible　studies　were　involved　in　this　meta-analysis.　The　synthesized　analysis　demonstrated　that　elevated　NLR　was　associated　with　poor　DFS　[HR=1.72,　95%　confidence　interval　(95%　CI)=1.30-2.27],　OS　(HR=1.87,　95%　CI=1.41-2.48),　and　cancer-specific　survival　(HR=2.09,　95%　CI=1.04-4.21).　The　correlation　was　stronger　in　triple-negative　breast　cancer　(TNBC)　(OS:　HR=2.58,　95%　CI=1.63-4.06;　DFS:　HR=3.51,　95%　CI=1.97-6.24).Conclusion:Higher　NLR　was　correlated　to　poor　prognosis　of　breast　cancer　patients.　As　a　clinical　parameter　that　we　can　easily　obtain,　NLR　might　be　a　potential　predictor　in　patients＇　survival　to　assist　with　physicians＇　treatment　decisions.