Abstract: Men with non-obstructive azoospermia might get their offspring with paternal genetic material by micro-injecting haploid spermatid into oocytes （round spermatid injection，ROSI；elongated spermatid injection，ELSI）. The haploid spermatid could be obtained from semen，testis biopsy specimens or in vitro culture of spermatogenic cells. But the fertilization rate and pregancy rate after micro-injecting with haploid spermatids were not satisfactory. In this paper，we discussed the ROSI/ELSI technique and its progress，the spermatid injection and activation，and its clinic application，as well as clinical and technical problems.

Key words: Azoospermia, Spermatids, Spermatogonia, Sperm injections, intracytoplasmic