We aimed to specifically identify the major egg yolk proteins (i.e. vitellogenin) in the amphipod Gammarus fossarum, a sentinel species in freshwater risk assessment. Vitellogenin production in female is vital for the embryonic development and its production in male organism is commonly employed as a biomarker of exposition to xenoestrogens in fish. We performed a shotgun proteomics analysis on embryos and ovaries at different stages of their development. The proteome dynamics over the cycle was analyzed to correlate on the first hand proteins which are accumulating along vitellogenesis and on the other hand, proteins with decrease amounts long embryogenesis. This information led to the proposal of putative novel VTG candidates. Our data provides the first large scale molecular description of a crustacean reproductive cycle, while our temporal analysis evidenced seven candidates proteins as “true vitellogenin” in G. fossarum.