We have identified two novel isoforms of fibroblast growth factor receptor‐4 (FGFR4). They result from alternative splicing of intron 17. Two transcripts, both slightly larger than the one coding for the known mouse FGFR4, are generated. The shortest (FGFR4‐17a) includes the 31‐most 3‐nucleotides of intron 17; the longest (FGFR4‐17b) includes all 114 nucleotides of intron 17. Translation of the FGFR4‐17a and FGFR4‐17b splice variants predicts that both novel putative FGFR4 isoforms have a truncated C‐terminal intracellular tail. The first amino acid residue affected by the insertions in both novel isoforms is Tyr‐760, a residue that may play a crucial role in intracellular signaling through stimulation of the phosphatidylinositol‐biphosphate pathway.