Food insecurity is one of the main factors affecting multimorbidity. Previous studies have shown that food insecurity may lead to multimorbidity due to person’s inability to consume nutritious diet. However, considering that multimorbidity may cause work-related disabilities and an unstable income, others support the possible effect that multimorbidity has on food insecurity. The purpose of this systematic review and meta-analysis is to examine the relationship between food insecurity and multimorbidity in adults. A systematic literature review of studies was performed using the PubMed, EBSCO and SCOPUS for all articles including adults ≥ 18-year-old with multimorbidity living in developed countries published from August 5thuntil December 7th2022. Meta-analysis was performed considering results from the fully adjusted model. The methodological quality was assessed using the Newcastle-Ottawa Scale adapted for cross-sectional studies. This systematic review was not registered. This research received no specific grant from any funding agency. Four cross-sectional studies involving 45,404 participants were included in order to investigate the possible impact that food insecurity has on multimorbidity. The study findings showed an increased probability of multimorbidity 1.55 (95% CI:1.31–1.79, p<0.001, I2= 44.1%) among people with food insecurity. Conversely, three of the included studies, involving 81,080 participants concluded that people with multimorbidity, have 2.58 (95% CI: 1.66–3.49, p<0.001, I2= 89.7%) times higher odds to present food insecurity. This systematic review and meta-analysis provide evidence of a reverse association between food insecurity and multimorbidity. Further cross-sectional studies must be conducted in order to elucidate the association between multimorbidity and food insecurity across age groups and between the two genders.