In this paper, an adaptive dynamic event-triggered asymptotic control scheme is designed for strict-feedback systems with time-varying parameters. The congelation of variables technique is employed to address the time-varying parameters in the system. During the controller design, two parameter estimation adaptive laws are constructed. The tuning function is introduced in the design process to avoid over-parameterization. To further conserve communication resources, a dynamic event-triggered approach is proposed, in which a non-negative variable is introduced to update the threshold parameter dynamically. The global uniform asymptotic stability of the closed-loop system is proven through the Lyapunov stability analysis. The feasibility of the scheme is demonstrated by simulation.