Differential pressure pipe sticking as one of the common borehole instability mechanisms occurs when the overbalance pressure pushing drill string toward filter cake. In this paper, the mechanism of releasing filter cake in low solid drilling fluid system based on bentonite is analyzed, and the dissolution of filter cake in different concentrations of sodium hydroxide solution is discussed through experiments. The results show that the combination of OH_- ^{with Ca}₂₊ ^{and Mg}_2⁺ increases with time, and reaches saturation after a period of time. Different concentrations of sodium hydroxide solution have different effects on filter cake. The application in well Wanbodi-1 shows that, compared with acid soaking and oil soaking, the treatment time of foam alkali is faster, which can avoid causing larger downhole complexity, reduce the interference to the subsequent drilling fluid and save the drilling cost. The results have a reference for the similar sticking processing.