Abstract Word learning requires establishing a mapping between words and concepts. Yet even before this mapping process, children need to attend to and identify conceptual units from perceptual inputs. From an associative perspective, attention is the initial step of early word learning, and differences in attentional patterns could play a role in language acquisition and development. English learners typically show vocabularies that are dominated by nouns, while studies reveal that verbs are acquired early and in large quantities by Mandarin Chinese learners. However, little research has examined whether English and Mandarin learners’ early comprehension and production of nouns and verbs could be attributed to attentional patterns. Thus, of interest for the present study is whether we will find fundamental differences in attentional patterns to complex scenes across developmental spans. In particular, we are interested in how the process of word learning may interact with attention among children who have not yet begun this process (i.e. 6 month olds) vs. children who are in the middle of an explosive phase of early vocabulary development (i.e. 18 month olds). In this study, we explore Mandarin-learning infants’ abilities to discriminate between Persons, Actions, and Objects in both silent and word-learning environments. 31 6-8 month and 48 17-19 month Mandarin-speaking infants were selected. Infants were randomly assigned to a habituation scene, in which a videotaped event of a young woman performing a novel action on a novel object was presented to infants in a habituation paradigm. These scenes were repeated over and over again until infants got bored. Once they were bored, infants were presented with four test trials, in which none (control trial) or one of the three elements changed (Person Change, Action Change, Object Change) with the other two held consistent with the habituation. Infants’ looking time was calculated on-line by a live experimenter who was blind to the stimuli appearing on the screen and coded the infant’s eye movement through a curtain hole. There was a main effect of test type (control, person change, action change, object change). The prediction of developmental differences in infants’ discrimination of the elements was also verified.These results revealed that 6-8 month olds allocated more attention to action change than control. In contrast, the 17-19 month olds paid more attention on all change trials than control. These studies aim to further investigate the cognitive mechanism underlying word-to-world mapping Some researchers have provided the evidence that Mandarin-speaking infants only learned word-action associations but not word-object associations. Not only could the present study help clarify and complement the previous findings, it contributes to the theoretical framework of word learning as a development process manifested at multiple levels. The current studies also provided the evidence in both the developmental changes in infants’ attentional patterns. Overall, 6-8 month olds could discriminate different actions, paying more attention to action change than control, but not different objects. In contrast, for the 17-19 month olds, they paid more attention on all change trials than control.