First lambing age and lambing interval are among the most important reproductive traits affecting profitability of sheep breeding systems. Genome-wide association studies (GWAS) were performed on estimated breeding values (EBVs) for age at first lambing and the lambing interval between first and second lambing in Lori-Bakhtiari ewes. Animals were genotyped using the Illumina Ovine SNP50 K genotyping array. Two single nucleotide polymorphisms (SNPs) associated with lambing interval were identified on chromosomes 1 and 2 (Bonferroni adjusted P-value<0.05). No SNP associated with first lambing age was detected. SNP s50067.1 on sheep chromosome 2: 86798921 is within a candidate gene; ADAMTS like 1 (ADAMTSL1), known to be involved in proteolysis, peptidase activity, biological process and reproductive pathways in mammalian species. No candidate gene was detected for SNP OAR1_57568179.1 on chromosome 1. The results of the present study may provide new insights into the genomic regions involved in reproductive traits of sheep.