Brazil is one of the largest producers and exporters of soybeans and its production is mainly transported via the road system. The growing concern on the impacts caused by anthropogenic greenhouse gas emissions from agroindustry production as well as the commitment to international treaties supports the relevance of controlling and estimating their emissions. The objective of this work is to calculate the emissions of the main sources of GHG in the cultivation and transport of soybean production in the macro-regions of Mato Grosso, pointing out the main routes and modal integration of the production sites to the main Brazilian ports. For this purpose, the Life Cycle Assessment methodology was adopted. The results show that in most cases, the production of one kg of soybean emits more CO2 than transportation of the same mass. This trend is more evident when the best actual combination of transportation modals is considered for each macro-region. The substitution of some highway stretch by water and/or railway has a positive effect, and it is possible to affirm that the use of multimodality, allows a significant reduction in CO2 emission.