The aim of this study was to analyze the modeling methodologies of fiscal policies on food with health or environmental outcomes. Evidence suggests that fiscal policies on food can contribute to addressing the growing burden of noncommunicable diseases and climate change. These policies should be modeled in advance to see the implications for the environment and health. A systematic review was conducted of studies that modeled fiscal policies on the food groups targeted by the EAT-Lancet Commission and examined their health or environmental outcomes. The Scopus and PubMed databases were searched on November 30, 2021. The records were double-screened and data on modeling methods were extracted from the included studies. A total of 55 studies were included in the review. The most frequently modeled interventions were fruit and vegetable subsidies (n = 19) and carbon taxes on food (n = 17). One study also included a consumer education campaign to enhance the effect of fiscal policy. The outcomes are highly sensitive to consumption change and price elasticities. None of the studies modeled the health effects of environmental outcomes. A model that covered all the relevant aspects of the issue was not found. Some parts were missing from all the included models. It is advisable to model the stability of the amount of diet consumed, either by keeping the amount of food in the diet stable or by taking a more conservative approach and keeping the consumed calories stable. It is preferable to keep the included diseases and environmental boundaries broad to have more valid outcome estimates on this complex issue. A more comprehensive understanding of fiscal policies would allow us to better anticipate the impact of our actions and inactions and thus could lead to more sophisticated measures taken by policymakers. PROSPERO registration no. 2022 CRD42022291945/.