Crossmodal correspondences refer to when specific domains of features in different sensory modalities are mapped. We investigated how vowels and lexical tones drive sound-shape (rounded or angular) and sound-size (large or small) mappings among native Mandarin Chinese speakers. We used three vowels (/i/, /u/, and /a/), and each vowel was articulated in four lexical tones. In the sound-shape matching, the tendency to match the rounded shape was decreased in the following order: /u/, /i/, and /a/. Tone 2 was more likely to be matched to the rounded pattern, whereas Tone 4 was more likely to be matched to the angular pattern. In the sound-size matching, /a/ was matched to the larger object more than /u/ and /i/, and Tone 2 and Tone 4 correspond to the large-small contrast. The results demonstrated that both vowels and tones play prominent roles in crossmodal correspondences, and sound-shape and sound-size mappings are heterogeneous phenomena.