The human homologue of the recently cloned murine IL‐13 binding protein (IL‐13Rα1) was cloned from a cDNA library derived from the carcinoma cell line CAKI‐1. The cloned cDNA encodes a 427 amino acid protein with two consensus patterns characteristic of the hematopoietic cytokine receptor family and a short cytoplasmic tail. The human protein is 74% identical to the murine IL‐13Rα1, and 27% identical to the human IL‐13Rα2. CHO cells expressing recombinant hIL‐13Rα1 specifically bind IL‐13 (K _d≈4 nM) but not IL‐4. Co‐expression of the cloned cDNA with that of IL‐4Rα resulted in a receptor complex that displayed high affinity for IL‐13 (K _d≈30 pM), and that allowed cross‐competition of IL‐13 and IL‐4. Electrophoretic mobility shift assay showed that IL‐13 and IL‐4 were able to activate Stat6 in cells expressing both IL‐4Rα and IL‐13Rα1, while no activation was observed in cells expressing either one or the other alone.