The invention relates to a binder, a preparation method of the binder and an application of the binder used as the metallurgical pellet binder, belonging to the technical field of the production of sintered pellets of the ferrous metallurgy. The technical scheme of the invention is as follows: the binder consists of the following one or two components: the mixture of polyacrylamide, sodium humate and nitrate or chlorate or perchlorate, corn starch mixture and the mixture of polyacrylamide and sodium aluminate. The preparation method comprises the following steps: adding the binder in fine iron powder for pelletizing of which 200-mesh passing rate is no less than 70% to mix evenly and pelletizing, wherein the dosage of the binder is 0.2-0.5% of fine iron powder. The invention has the beneficial effects: the binder has some properties of bentonite such as hygroscopicity and lubricity, the binder does not contain silicon, aluminum, phosphorus and sulfur, the pelletizing dosage of the binder is small, the burning loss is high, the high temperature burning loss of the binder is up to 60%-90%; and the pelletizing process mainly adopts lamellar packing growth, the agglomeration growth is reduced, the internal oxidation of the pellets in the chain grate can be promoted.