Over the last decade, Psidium guajava L. (guava) leaves have demonstrated their in vitro and in vivo effect against Diabetes mellitus (DM). However, there is a lack of literature concerning the effect of the individual phenolic compounds present in the leaves in DM disease. For this reason, the aim of the present work was the in silico evaluation of each phenolic compound. The identification of an 80% ethanol extract of guava leaves revealed the presence of 73 compounds. The in silico study carried out with the DIA-DB web server revealed that aldose reductase was the target protein with heterogeneous affinity. Naringenin exhibited the highest number of interactions with target proteins, and compounds like catechin, quercetin, naringenin and morin displayed similarities with known antidiabetic drugs. In conclusion, the computational workflow showed that guava leaves contain several compounds that can play a therapeutic role in the treatment of DM.