AbstractDespite extensive research on theba-construction in Chinese, the diachronic change in the alternation between thebaandjiangconstructions has received little attention. The present study takes a multifactorial approach to examine the factors that probabilistically condition the alternation based on diachronic data across twelve centuries. The results suggest two general trends. First, the odds of theba-construction have increased over time at the expense of thejiang-construction. Second, over time, the effect size of the significant preference for thejiang-construction in informal genres has reduced from the 10th to the 19th century, and this preference has disappeared in modern times; accordingly, both informal and formal genres have converged to favor theba-construction in modern times. Regression modeling also shows that there are both stable linguistic constraints (parallelism/syntactic priming, verb type, NP2 animacy, and NP2 length) and fluid constraints (adjunct semantics, and genre). This study advances our knowledge of the two disposal constructions and their evolution, sheds light on the Principle of No Synonymy (Bolinger, Dwight. 1977.Meaning and form. New York: Longman; Goldberg, Adele E. 1995.Constructions: A construction grammar approach to argument structure. Chicago: The University of Chicago Press; Goldberg, Adele E. 2002. Surface generalizations: An alternative to alternations.Cognitive Linguistics13(4). 327–356), and makes a methodological contribution to the empirical testing of hypotheses. It can also provide insight into grammatical alternations in Mandarin.