This dissertation examined the role of maternal input in word order acquisition of Mandarin-speaking children from the one-word to multi-word stages. Four questions about the role of maternal input were addressed: frequency effects, age-related changes, utterance type effects, and verb diversity effects. Predictions for each question were made based on the generativist and constructivist accounts. Spontaneous speech of 40 Mandarin-speaking mother-child dyads selected from CHILDES Zhou corpus, with 10 dyads in each of four age groups: 14-, 20-, 26-, and 32-month-olds, were coded for word order, utterance type, and verb type. Both maternal and child distributions were compared for analyses. Mothers across all four age groups produced a variety of word orders and constructions in their speech. Frequency effects were found in most child word order uses but not in the Ba and different multiple-verb constructions. Most child word order uses reached adult levels of frequency at either 26 or 32 months. Maternal speech did not show age-related changes as child production grew from one word to multi words. No significant relationship was found between mothers and children in most word orders. Utterance type effects were not found because mothers used different word orders for different utterance types while child production did not reflect this tendency. The distribution of verb diversity within maternal and child word orders shared a similar pattern. Word orders with greater verb diversity tended to be acquired earlier. The findings that frequency effects and verb diversity effects were found in early word order acquisition support both generativist and constructivist claims. The lack of age-related changes and utterance type effects in maternal word order uses is contrary to the constructivist view. Although maternal input (e.g., frequency and verb diversity) may play a role in acquisition of Mandarin word order, there are possible influences other than input. These influences may include child linguistic competence, linguistic complexity of constructions being learned, and semantic/pragmatic factors that constrain the choice of word order. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]