A seed-covering agent, which is used for covering a seed surface and which contains an iron powder and a binder, is specified in such a way that, in the above-described iron powder, the mass ratio of an iron powder having a particle size of 63 µm or less to a total mass of the iron powder is 0% or more and 75% or less, the mass ratio of an iron powder having a particle size of more than 63 µm and 150 µm or less to the total mass of the iron powder is 25% or more and 100% or less, and the mass ratio of an iron powder having a particle size of more than 150 µm to a total mass of the iron powder is 0% or more and 50% or less, and the average particle size of the above-described binder is 1 to 150 µm. Consequently, a cover with reduced falling of the iron powder in not only a seeding step, but also a transportation step can be realized.
