Problem To provide: a steelmaking slag coated seed which can be provided with a steelmaking slag coating layer of a uniform and sufficient amount and which requires less labor by an operator and for which low cost production is possible； and a production method therefor. Solution A steelmaking slag coated seed has a seed such as rice and a steelmaking slag layer formed on the outside of the seed. The steelmaking slag layer is a coating layer comprising a steelmaking slag powder formed by pulverizing steelmaking slag. The steelmaking slag contains a calcium content of at least a prescribed amount with respect to all components of the steelmaking slag.
