Prior to the deal, Alibaba held 47 percent of Cainiao, it said in a press release. The deal would give Alibaba an additional seat on Cainiao's board, raising its total to four out of seven seats.
The deal is expected to be completed in October.
Alibaba added that it expects to invest 100 billion yuan, or $15.2 billion, over the next five years to boost its global logistics network. The company said it wants to fulfill orders on the mainland withing 24 hours and within 72 hours globally.