Spermatogonial stem cells (SSCs) are the germ stem cells of the seminiferous epithelium in the testis. Through the process of spermatogenesis, they produce sperm while concomitantly keeping their cellular pool constant through self-renewal.

Spermatogonial stem cells are the precursors to spermatozoa, which are produced through a series of differentiation steps. This is the alternative SSC outcome to self-renewal. SSCs survive within microenvironments, termed niches, which provide extrinsic stimuli that drive stem cell differentiation or self-renewal.