A method of manufacturing a wiring substrate having a wiring layer formation step that includes: a first surface processing step in which surface processing is performed on a film formation area of a substrate; a wiring formation step in which a wiring pattern is formed by placing a first liquid material on the film formation area; a second surface processing step in which surface processing is once again performed on the film formation area; and an insulating film formation step in which an insulating film is formed by placing a second liquid material in gaps in the wiring pattern, wherein an affinity between the second liquid material and the film formation area in the insulating film formation step is greater than an affinity between the first liquid material and the film formation area in the wiring formation step.