The objective of this research is to improve the efficiency of cold rolling of thin steel sheets with a thickness of 1.5 mm by determining efficient deformation degree. Low-carbon steel 20 was used for the research, and reduction patterns under conditions of cold rolling were determined. While maintaining a constant final sheet thickness of 1.5 mm, the deformation degree was observed to vary based on the initial thickness of the semi-finished rolled product. Key parameters, such as the initial temperature and rolling speed, were adjusted at 200°C and 1 m/s, respectively. The strip width was maintained as a constant, and a friction coefficient of 0.01 was adopted. The research delved into the deformation zone formed during longitudinal sheet rolling, defining its coefficients and essential parameters. Additionally, factors influencing the quality of the resulting sheet were identified. The research also explored the influence of the deformation degree on metal stress during the cold rolling process of thin sheets. This involved an analysis of yield strength, metal flow, and overall strength. Furthermore, the study established the rolling force and its variations with changing deformation degrees. An integral aspect of the study was the examination of the impact of the deformation degree on the process productivity of cold-rolled thin sheets. Through comprehensive analysis, a rational deformation degree was pinpointed, ensuring the production of a high-quality product with efficient strength and plasticity. This optimized degree also minimizes the required deformation forces and rolling torques, contributing to maximum process productivity.