Aim: To characterize the coexpression of survivin, an inhibitor of apoptosis (IAF), and human telomerase reverse transcriptase (hTERT) in human testes with varying spermatogenic function. Methods: Transcript levels of survivin mRNA and hTERT mRNA were determined in normal testes (n = 11) and testes with defective spermatogenesis (n = 28) using real-time reverse-transcription polymerase chain reaction (RT-PCR). The histological work-up was performed according to a modified Johnsen score. Results: Expressions of both survivin and hTERT were highest at median levels of 96.8 and 709 in normal spermatogenesis and dropped to 53.3 and 534 in testes with postmeiotic spermatogenic arrest (n = 10). In severe spermatogenic failure (n = 18), survivin expression was lacking in most specimens (n = 16), whereas at least low levels of testicular hTERT expression were largely detectable with a normalized expression of 73 in premeiotic spermatogenic arrest (n = 7) and 45 in patients with Sertoli cell-only syndrome (SCOS)(n = 3). Both survivin and hTERT expressions increased with a progressing Johnsen score (P for trend = 0.001).Conclusion: Although both survivin and hTERT are correlated with spermatogenic function, they show different expression patterns in testes of infertile patients. These findings substantiate results from studies in the rodent testis suggesting a predominant expression of survivin in meiotically dividing germ cells.