Versatile Video Coding (VVC) has set a new milestone in highefficiency video coding. In the standard encoder, the -domain rate control is incorporated for its high accuracy and good Rate-Distortion (RD) performance. In this paper, we formulate this task as a Nash equilibrium problem that effectively bargains between multiple agents, i.e., Coding Tree Units (CTUs) in the frame. After that, we calculate the optimal value with a two-step strategy: a Newton method to iteratively obtain an intermediate variable, and a solution of Nash equilibrium to obtain the optimal . Finally, we propose an effective CTU-level rate allocation with the optimal value. To the best of our knowledge, we are the first to combine game theory withdomain rate control. Experimental results with Common Test Conditions (CTC) demonstrate the efficiency of the proposed method, which outperforms the state-of-the-art CTU-level rate allocation algorithms.