An upper iron and a lower iron of a trouser-pressing machine. The trouser-pressing machine has an upper iron, a lower iron and a middle iron, and forms can be press both legs of a trouser at a time. In the covers of the present invention, inside peripheral parts of main parts of covers are formed non-porously corresponding to pressing surfaces of the upper iron and the lower iron. In the present invention, the part formed non-porously can be not only the entire inside peripheral parts but also the portions corresponding to one side end of the middle iron on which the crotch of the trouser is set.