As happened in West Africa in 2008, in an imported inflation context, it is common for the governments to take short-term tax action to protect the poor: VAT or trade tariffs exemptions. As part of the tax-tariff transition, the comparison between Trade tariffs and VAT has already been the subject of much works. The introduction of VAT, as a tax on final consumption, is supposed to be optimal, due to its economically neutral aspect for production decisions. However, some authors show that in developing countries, a large informal sector affects this result. In this paper, we use a CGE model and a micro-simulation model to compare the effects of VAT and Trade tariffs exemptions to combat rising agricultural food prices.