The present studies sought to investigate the mapping relations between language and cognition by focusing on how Mandarin-speaking children acquire the mapping between their conceptual knowledge of possession and their linguistic expressions of possession. Two experiments were conducted. Experiment 1 used a comprehension task to explore whether young children are able to map their knowledge of possessive constructions onto their interpretation of possessive relations. Experiment 2 employed a production task to examine whether they are able to map their knowledge of possessive relations onto their linguistic expressions of possession. The findings were that 4-year-olds exhibited correct comprehension and production of possessive DE constructions, indicating that by age 4, Mandarin-speaking children have already established the mapping between their conceptual knowledge of possession and their linguistic expressions of possession. By contrast, 3-year-olds exhibited response patterns that suggest a developmental stage where they use noun-noun compounds to represent possessive relations before they map possessive relations onto possessive constructions.