Abstract: A gene encoding ferritin was isolated and cloned from B. microplus. The cDNA is composed of 642 nucleotides and encoding 172 amino-acid residues, the encoding region is between 123 bp to 639 bp, the deduced mass is 19.9ku and isoelectric point is 4.24.The deduced amino-acid sequence shows 93.60%, 88.37% and 83.72% similarities with the ferritin from tick Dermacentor variabilis, Ixoded ricinus, and Ornithodoros moubata respectively. The stem-loop structure of a putative iron responsive element is found in the 5-untranslated region of ferritin mRNA. The protein contains the conserved motifs for ferroxidase center. RT-PCR analysis suggests the ferritins are expressed in the eggs，larvas，fed female adult，engorgement female adult and male adult ticks of B. microplus.