Pairs of forward and reverse primers and TaqMan probes specific to each of 173 human solute carrier (SLC) transporters were prepared. The mRNA expression level of each target transporter was analyzed in total RNA from single and pooled specimens of various human tissues (adrenal gland, bladder, bone marrow, brain, colon, heart, kidney, liver, lung, mammary gland, ovary, pancreas, peripheral leukocytes, placenta, prostate, retina, salivary gland, skeletal muscle, small intestine, smooth muscle, spinal cord, spleen, stomach, testis, thymus, thyroid gland, trachea, and uterus) by real-time reverse transcription PCR using an Applied Biosystems 7500 Fast Real-Time PCR System. Individual differences in the mRNA expression of human SLC transporters in the liver were also evaluated. These newly determined expression profiles were used to study the gene expression in the 28 different human tissues listed above, and tissues with high transcriptional activity for human SLC transporters were identified. These results are expected to be valuable for research concerning the clinical diagnosis of disease.