The deep mixing method (DMM) has been applied in many construction projects for various improvement purposes. Laboratory mix test is essential to quality control and quality assurance (QC/QA) of deep mixing methods. The procedures used for the preparation of specimens in the laboratory mix test greatly affect the physical and mechanical properties of the stabilized soils. Different procedures are applied in different countries/regions. With the increasingly globalizing DMM market in the background, it is desired to establish common understanding of the nature of laboratory mix test and internationally accepted guidelines to conduct them, in order to guarantee the QC/QA of DMMs. As part of an international collaborative study, the influence of different molding techniques for the laboratory preparation of specimens was studied. The applicability of the molding techniques was analyzed by two indices, the undrained shear strength and the liquidity index of the soil and binder mixtures before molding. The results showed that the molding techniques considerably influenced the magnitude and variation of the unconfined compressive strength and the wet unit weight of the stabilized specimens.