Chalcones, a class of natural compounds, characterized by having an α, β-unsaturated carbonyl linking two aromatic rings in their structure, are compounds of great biological relevance and wide variety of biological activities, being important research objects, which is why their obtainment synthetically have great relevance, being a more promising alternative than natural extractivism. Thus, this work aimed at the synthesis and structural elucidation of isoliquiritigenin, (2E)-1-(2,4-dihydroxyphenyl)-3-(4-hydroxyphenyl) prop-2-en-1-one, using aldol condensation Claisen-Schmidt type in basic medium (KOH) of the acylated resorcin (1-(2,4-dihydroxyphenyl) ethan-1-one) with p-hydroxyaldehyde, being possible its identification by means of ¹H and ¹³C NMR spectra.