Briquetting is an important process for the treatment of zinc-containing dust in the rotary hearth furnace process， and there are such problems as low strength of wet agglomerates，expensive binders，and easy breakage of agglomerates during belt transfer. In this paper， conventional modified starch is used as a binder to participate in briquetting of zinc-containing dust mixtures，and the effects of moisture， roller speed， inter-roller pressure and binder dosage on the strength of the briquettes are explored，and the action mechanism of the binder is explained by group behavior analysis，infrared spectroscopy analysis，and XPS photoelectron spectroscopy. The results show that when the amount of modified starch is added at 2%， the briquetting strength is similar to that when the binder is 3.5%， the cost of binder is reduced by 53 yuan/t. Continuing to increase the amount of binder can greatly improve the briquette strength，and the briquette strength achieves the optimal value when the amount of modified starch is 3.5%. At this time，the falling strength of the wet briquette is 7.80 times/(0.5 m)， the compressive strength is 91.78 N/P，and the compressive strength of the dry briquette is 388.55 N/P. The mechanism of pregelatinized starch to improve pellet strength is analyzed，and it is found that the characteristic absorption peaks of dry ball powder at 1 404 cm^-1 and 860 cm^-1 are significantly enhanced after the addition of starch，and the characteristic absorption peak of —OH relative to Fe translation appeared at 549 cm^-1. Photoelectron spectroscopy shows that the 2p orbital energy of Fe is decreased from 719.7 eV to 719.35 eV after the addition of starch， indicating that the polar groups in starch are adsorbed with the surface of zinc-containing dust，which is the key factor for the increase of briquetting strength. The research results can lay a foundation for the low-cost and efficient treatment of zinc-containing dust in the rotary hearth furnace and the development of the rotary hearth furnace process.