Our study examined the reproducibility of the Biginelli reaction under various conditions using different catalysts. Seven experiments were conducted using benzaldehyde, urea, and ethyl acetoacetate with different catalysts such as HCl, ZnBr2, NH4Cl, LiBr, InCl3, CaF2, and CuI. The results showed that reactions with HCl, ZnBr2, and NH4Cl were reproducible, while those with LiBr, InCl3, CaF2, and CuI showed significant deviations from literature values. The reproducibility of the reaction can be affected by the choice of catalyst and reaction conditions. Some catalysts, such as CaF2 and CuI, were found to be ineffective under the tested conditions. These results draw attention to the fact that reproducibility of experiments described in the chemical literature is not always straightforward.