Cloning and sequence characterization of four important genes (actin, ultra spiracle proteins, tyrosine hydroxylase and vATPase B) from Plutella xylostella are compared with other species of Lepidoptera. Sequence analyses showed variation of the genes within Lepidoptera and the number of parsimony informative sites observed in nucleotide sequences was 151, 426, 502 and 103 for actin, ultra spiracle proteins, tyrosine hydroxylase and vATPase B respectively. Phylogenetic analysis indicated that actin and vATPase B are highly conserved across Lepidoptera. This analysis is useful in understanding the genetic relationship among various Lepidopteran insect and thereby providing insight into the genetic structure. This can establish a critical basis for analysis of biological functions in insects using novel approaches such as RNA interference (RNAi).