A mounting substrate includes a through-hole 13 formed in a substrate 10, a first land part 21, a second land part 31, a first component attaching part 22, a second component attaching part 32, a conductive layer 14, and a filling member 15 filled into a part of the through-hole 13. A shortest distance allowable value L0 from the center of the first land part 21 to a component 51 is determined on the basis of the volume Vh of a part of the through-hole 15 positioned above a top surface of the filling member 15 on the side of the first land part 21, the length L1 of the component 51 to be mounted to the first component attaching part 22, and the maximum allowable value of the inclination of the component 51 to be mounted to the first component attaching part 22 relative to the first surface 11 of the substrate 10.