ATP-citrate lyase (ACLY) is a key enzyme that links carbohydrate and lipid metabolism. Understanding the catalytic mechanism of ACLY can aid in drug development to decrease lipid production as a possible treatment for obesity and cancer. The goal of this study was to determine the structure of the carboxy(C)-terminal portion of Chlorobium limicola ACLY (ClACLY). A tobacco etch virus protease site was introduced into ClACLY so that the N- and C-terminal portions could be separated after cleavage. A 1.9 Å dataset was obtained from a crystal of the C-terminal portion of ClACLY co-crystallized with acetyl-CoA. The structure revealed that the C-terminal portion was the oligomerization site for ACLY and contained the CoA-binding site. The results of this study further advance the knowledge of how the C-terminal portion of ACLY participates in catalysis.