Haemaphysalis longicornis is one of the most important tick species distributed globally. It transmits various pathogens that cause great damage to human health, livestock production, and wild animals. Knowledge of the character of transferrin (Tsf) in insects has grown rapidly during the last decades. However, Tsf in ticks is still poorly understood. Here, we identified for the first time a new iron metabolism-related gene, namely, Tsf, in ticks. The open reading frame (ORF) of the Tsf gene in H. longicornis contained 2,412 bp, which encoded a protein of 803 amino acids.