In the mid-to-late stages of offshore gas field production, issues such as severe water breakthrough and sudden gas production decrease often occur, leading to liquid accumulation problems. Research is needed to study the on-site liquid accumulation behavior, assess liquid accumulation risks, and determine the timing for gas recovery by liquid unloading measures. Establish a transient/steady-state mutual verification wellbore model, and use on-site statistical wellhead temperature, pressure, and production parameters to invert the sedimentation process of produced water and the dynamic equilibrium process of reservoir-wellbore-surface. Then analyze the variation law of the actual liquid loading velocity ratio (LLVR), and form an optimized method for determining the risk of liquid accumulation. The results indicate that (1) the conventional steady-state fluid accumulation model believes that LLVR > 1 is the principle for risk assessment, which is relatively conservative. (2) When the gas well is in a stable production stage and the gas and water production at the wellhead can maintain stable production, it is considered that the risk of liquid accumulation is low and in a controllable state, and drainage measures may not be taken. (3) When the gas well is in the critical production stage and the water and gas production at the wellhead slowly decrease, it is considered that the risk of liquid accumulation has reached a critical state, and timely drainage measures should be taken. (4) When the gas well is in the area of liquid accumulation and the water and gas production at the wellhead sharply decrease, it is considered that the accumulated liquid has crushed the formation, and immediate drainage measures should be taken. The above research can provide a certain theoretical basis for determining the timing of liquid accumulation in offshore gas fields and designing drainage and production plans.