Sulfide minerals are critical targets in non-ferrous metal flotation, and their flotation efficiency is of significant interest. This study investigates the effects of pulp concentration, fineness, associated minerals, collectors, and frothers on the surface tension of the pulp through surface tension measurements, with pyrite and pyrrhotite as the research objects. Pure mineral flotation tests further explore how pulp surface tension influences the flotation recovery rates of these two minerals. The test shows that surface tension initially decreases and then increases with rising pulp concentration, with an optimal pulp concentration of 30 % for both minerals; decreasing particle size significantly reducespyrite's surface tension, while pyrrhotite remains relatively unaffected; galena exhibited the Iowest surface tension among common associated minerals; MA-1, the prioritized collector, optimizes pyrite recovery while Iowering pulp surface tension; while butyl xanthate most effectively reduces pyrrhotite's surface tension and enhances its recovery; the frothers, HX-609 (for pyrite) and No. 2 oil (for pyrrhotite), achieve maximum recovery and minimal pulp surface tension at low dosages. Analysis confirms that reduced pulp surface tension correlates with markedly improved l recovery rates for pyrite and pyrrhotite. Thus, Iowering pulp surface tension presents a viable strategy to enhance sulfidemineral flotation efficiency.