Necessary literal checking is an important preprocessing technique. by learning clauses, this paper proposes a clausebased dynamical necessary literal checking strategy (CNL) used in the solving process, and designs a lowcost data structure.  We implement two solvers, Glucose_PRE and Glucose_CNL. The former adopts the necessary literal checking as the preprocessing technique at the beginning of the solving process, and the latter implements the proposed clausebased dynamical necessary literal checking strategy. Experimental results show that the Glucose_CNL solves more instances with less time than the Glucose_PRE and Glucose 3.0 when solving the applicationtype instances in 2015 and 2016 SAT competitions, demonstrating the significance of the proposed strategy and data structure.