To prevent weakly flocculating characters of bottom brewing yeast during first fermentation, various technical investigations were carried out using strain of Saccharomyces cerevisiae. It appeared that the propagation at $10^{circ}C$ promoted the molecular structure and biochemical composition of cell wall in favor of flocculation. The yeast grown at $20^{circ}C$ by addition of zinc ion also had a stimulating effect on flocculation behavior during first fermentation cycle. The zinc ion did not influence directly on the changes of cell wall in favor of stronger flocculence. The increased fermentation activity of yeast due to addition zinc ion was rather responsible for the intensified flocculation capacity. It was concluded that the weakly flocculating characters of bottom brewing yeast during first fermentation can be solved by using yeast propagated at $10^{circ}C$ or by means of yeast by addition of zinc ion during propagation.