The Payment for Forest Ecosystem Services (PFES) policy in Vietnam is a multi-objective policy that aims to both protect forests and ensure sustainable livelihoods for local people. As such, to evaluate the effectiveness of this policy, we are facing the problem of multi-criteria decision-making (MCDM). The objectives of this paper are to assess PFES at a community level through the application of the TOPIS model to solve an MCDM problem and examine factors correlating to the effectiveness of the policy. The study is conducted in the Northwest regions of Vietnam. Using TOPSIS model and fuzzy entropy to create a single aggregation score measuring the policy outcomes, this paper has ranked the level of PFES effectiveness in studied villages and identified factors that significantly correlate to this policy’s effectiveness at the grass-root level. Among the interesting factors, cash payments, community involvement, and the transparency of PFES implementation are the most important ones that determine PFES’s success.