Alfalfa weevil is an invasive pest of several leguminous plants. In the world preservative, there is a lack of information about the level of differentiation among separate populations. We ran a comparative molecular and ecological analysis to assess diversity, phylogenetic relationship and also simplify the taxonomic decisions. By analyzing a total of 147 specimens from Middle East, Europe and America plus a few sequences in GenBank we improved our current knowledge of world phylogeography of Hypera postica. The result of mitochondrial genes (Summation of COI and CytB) revealed a deep divergence between two previously defined clades (5.6 – 6.7% nucleotide divergence) within sympatric distribution. The Eastern lineage comprised 60 haplotypes in Iran and 3 haplotypes in Italy with respectively 0.07 – 2.2% and 0.2 – 3.4% sequence divergence range. On the other hand, the Western lineage which was detected in Poland, Czech and Western America had relatively lower haplotype diversity presenting a total of 11 haplotypes and 0.1%-1.1% sequence divergence. The coexistence of two lineages in some regions led to the huge overlap in their fundamental nich, but also a certain level of divergence can be detected via ecological nich modeling analysis.