This study investigated how a representative sample of 492 Cantonese-speaking children aged 36, 48 and 60 months expressed time during naturalistic conversations with peers. Spontaneous utterances produced by dyads of children in a 30-minute role-play context were collected, transcribed and analyzed. A productive repertoire of 62 nouns, 69 adverbs and 9 aspects was identified and classified into a typology. An age-related increase in types of temporal noun and adverb and repertoire size was found. It was also discovered that three-year-olds might already possess knowledge of aspect markers even though they might not be able to produce temporal nouns about “season” and “week” before 4 or 5 years of age. Some instances of double aspectual marking and misplacing aspects were found in the expressions. Linguistic, cognitive and conversational influences presumed to shape performance are discussed together with the implications of the findings for early childhood language education.