Abstract: In order to explore the function of IGF1R during the process of the growth and development in Tegillarca granosa, Tg-IGF1R cDNA was cloned by SMART RACE (Rapid Amplification of cDNA Ends) techniques on the basis of cDNA library of T.granosa. The full length cDNA of Tg-IGF1R was 5793 bp, and its complete ORF (Open Reading Frame) was 4638 bp encoding 1546 amino acids. Bioinformatics analysis showed that the sequence of Tg-IGF1R contains a 5'-untranslated region (UTR) of 810 bp, and a 3'-UTR of 345 bp. The predicted molecular mass of the deduced amino acid of Tg-IGF1R was 176.01 ku, and the theoretical isoelectric point was 6.04. Tg-IGF1R protein consists of four fibronectin type Ⅲ(FN3) domains, one furin like cysteine-rich (FU) domain and Tyrosine kinase (TyrKc) domain, belonging to transmembrane and hydrophilic protein. Homologous analysis on the amino acids showed that IGF1R of T. granosa shared more than 40% similarity with the most species of IGF1R, including Homo sapiens, Xenopus laevis, and Danio rerio. qRT-PCR (Real-time quantitative PCR) results indicated that Tg-IGF1R gene was expressed in 6 tissues (blood, adductor muscle, foot, gill, visceral mass and mantle.), and the expression of blood was significantly higher than other tissues, which implied that Tg-IGF1R plays various biological roles. The results of relative expression in 9 development stages revealed that the expression of Tg-IGF1R gene showed the highest expression in the gastrulae stage, and followed by trochophore and juvenile clams stages. Therefore, Tg-IGF1R may be involved in the formation of certain organs in early developmental stages.