As a member of the T cell immunoglobulin domain and mucin domain (TIM) gene family, TIMD4 plays an important role in the immune response. To understand its function more precisely, we isolated it and analyzed its subcellular localization, expression pattern, and associations. The porcine TIMD4 gene included nine exons and eight introns with an open reading frame of 1086 bp encoding 361 amino acids. It had relatively high levels in liver, lymph, and spleen. The fusion protein was localized mainly in the cytoplasm of pig kidney cells (PK15). The promoter region contained a TATA box and GATA3 consensus sites. A single nucleotide polymorphism was identified in intron 3 of the porcine TIMD4 gene, and analysis indicated that it had significant associations with the 17-day red blood cell count (p = 0.0106), hemoglobin (p = 0.0149), and hematocrit (p = 0.0063) and with 32-day hemoglobin (p = 0.0140).