Human stem cell-derived blastoids display similar morphology and cell lineages to normal blastocysts. However, the ability to investigate their developmental potential is limited. Here, we construct cynomolgus monkey blastoids resembling blastocysts in morphology and transcriptomics using naive ESCs. These blastoids develop to embryonic disk with the structures of yolk sac, chorionic cavity, amnion cavity, primitive streak, and connecting stalk along the rostral-caudal axis through prolonged in vitro culture (IVC). Primordial germ cells, gastrulating cells, visceral endoderm/yolk sac endoderm, three germ layers, and hemato-endothelial progenitors in IVC cynomolgus monkey blastoids were observed by single-cell transcriptomics or immunostaining. Moreover, transferring cynomolgus monkey blastoids to surrogates achieves pregnancies, as indicated by progesterone levels and presence of early gestation sacs. Our results reveal the capacity of in vitro gastrulation and in vivo early pregnancy of cynomolgus monkey blastoids, providing a useful system to dissect primate embryonic development without the same ethical concerns and access challenges in human embryo study. Display omitted •Generation of cynomolgus monkey blastoids using naive ESCs and optimized protocol•Monkey blastoids showed similar morphology and lineage composition to blastocysts•In vitro cultured monkey blastoids recapitulate gastrulation to three germ layers•In vivo transplantation of monkey blastoids triggers pregnancy with gestation sacs Stem cell-based embryo models provide a useful system for studying early embryonic development. Li and colleagues reported the generation of cynomolgus monkey blastoids with similar characteristics to natural blastocysts. These blastoids possess the capacity of in vitro gastrulation with three germ-layer differentiation and in vivo early pregnancy with gestation sac.