To investigate the developmental patterns of the learning of Putonghua (PTH) by preschool children from the Uygur ethnic group in kindergarten in South Xinjiang Uygur Autonomous Region, a speech corpus was established concerning the development of phonology and sentence structures of PTH. Regarding the phonological development, both segmental and prosodic development were examined. For segmental aspect, the production of monosyllabic and disyllabic words was elicited in a picture-naming task for PTH-learning preschoolers in the first (33 children) and second (66 children) year in kindergarten. For prosodic aspect, the production of broad focus with a statement intonation and the production of contrastive focus in different positions in a sentence with either a declarative statement intonation or a declarative question intonation was elicited in a two-task session, the question-and-answer task and the picture-guessing task, for PTH-learning preschoolers in the second (60 children) and third (60 children) year in kindergarten. In terms of the development of syntactic structures, the production of basic sentence structures of PTH was tested in a question-and-answer task for PTH-learning preschoolers (66 children) in the second year in kindergarten. And the mastery of basic sentence structures of PTH was also tested in a two-task session, the shadowing task and the picture-describing task, for PTH-learning preschoolers (84 children) in the third year in kindergarten. The speech samples collected can be contributed to exploring the mechanism of learning a second language during the preschool period and the relevant factors that influence second-language learning.