Abstract: We evaluated on operational effect and economic performance of five medium loaders with seeding in tobacco seedling production with floating system. The results showed that the machines could reduce labor cost up to 31%, but the reduction varied with machines. Overall, type I and IV machines had the best effect. Type I machine could fill medium just fine, sow seeds with high precision, operate efficiently with functions of lifting, disk mounting, disk loading, disk surface cleaning, pot pressing, sowing and covering. The design of type I was reasonable and its high degree of automation was suitable for large-scale seedling production. The type IV machine had moderate medium filling capacity, with high precision seeding, surface clean facility, and low noise, low power consumption and simple operation, which were suitable for small seedling production workshop.