The French language has a grammatical gender system in which all nouns are assigned either a masculine or a feminine gender. Nouns provide two types of gender cues that can potentially guide gender attribution: morphophonological cues carried by endings and semantic cues (natural gender). The first goal of this study was to describe the acquisition of the probabilistic system based on phonological oppositions on word endings by French-speaking children. The second goal was to explore the extent to which this system affects categorization. In the study, 3- to 9-year-olds assigned gender categorization to invented nouns whose endings were typically masculine, typically feminine, or neutral. Two response conditions were used. In the determiner condition, children indicated the gender class by orally providing the determiner un or une marked for gender. In the picture condition, responses were given by pointing to the picture of a Martian-like female or male person that would be best called by each spoken pseudoword. Results indicated that as young as 3 years, children associated the determiner corresponding to the ending bias at greater than chance levels. Ending-consistent performance increased from 3 to 9 years of age. Moreover, from 4 years of age onward, sensitivity to endings affected categorization. Starting at that age, pictures were selected according to endings at greater than chance levels. This effect also increased with age. The discussion deals with the mechanisms of language acquisition and the relation between language and cognition.