Abstract: Effective mass of non-uniform objects varies differently and indivisibly, thereby making the combined object uncertain during the combined weighing and quantification process. Thus, there is a great contradiction between the quantitative accuracy of combined weighing and combined speed. In this study, a chain-drive combination weighing and quantitative system was proposed, where the precision-efficiency was treated as the combined operation target. A combined error of influence parameters was analyzed to evaluate the accuracy of combined weighing quantification. Besides, the number of combined samples and sampling were optimized to reduce the combined calculation time with a high combined quantitative speed. The results indicated that the number of combined samples increased the probability of combination success. However, the amount of combined calculation increased exponentially with the increase of the number of combined samples. Thus, the number of combined samples needed to be optimized for the tradeoff between the combined error and calculation time. A normal distribution was followed after 10 000 rounds of combined calculation on the quality data, where the mean value was equal to 100, and the variance was 102. It was found that the number of combined samples was 14 with the shorter calculation time when the target mass of combined quantification was 500 g and the allowable combined error was ±0.1 g. Moreover, the sampling numbers needed to be screened for the high requirements of combined error, due to the characteristics of non-uniform objects. In addition, a simulation experiment was designed to explore the influence of the total sampling number on the combined error and calculation time. The test results showed that the improved and previous combination maintained the success probability of quantitative combination at about 95% when the standard deviation of weight distribution was less than 30 g and the combined quantitative error was less than 0.1-1.0 g. The calculation time of the optimized combination was reduced by 40%, compared with the conventional one. The findings can provide a sound reference for the potential development of a chain combined weighing and quantitative system for non-uniform objects.