Background and Objectives: Objects of the research in this study are solutions of bovine serum albumin (BSA) and its aggregates. Structural changes of the protein molecules in solution with pH 3 and pH 7.4 are investigated during glycation and thermal denaturation processes, when the BSA molecules in solution undergo similar intermediate states. The main aim of the research is to compare structural changes of the BSA upon its glycation and thermal denaturation, revealed by combination of optical and X-ray techniques.