Formal contacts between the Qing Dynasty and the KazakhKhanate started in the mid一Qianlong period. This article uses Manchu archives stored in the First Historical Archives of China as the core material in combination with related historical resources，to analyze diplomatic contacts between the Qing Dynasty and the leader of the left branch of the Kazakhs，Abulai，and major leaders of the right branch of the Kazakhs，to demonstrate that from the earliest times the Kazakhs showed their willingness to submit to the Qing Dynasty by sending envoys. The author analyzes the process of the Qianlong Emperor’schanging policy towards Kazakh. Building on the foundation of previous studies，most of which agree on the direct contact between Qing Dynasty and Kazakh Khanate began in 1755. This paper advances new arguments on the specific timing of the submissions of left branch of the Kazakhs，right branch of  the Kazakhs submitted to Qing Dynasty，the identities of specific envoys，and the desire of Abulai and his realistic consideration regarding submission to the Qing.