A multilayer wiring board with built-in electronic components includes a substrate including an insulating material and having multiple opening portions, a first conductor layer formed on a surface of the substrate and having an opening portion such that the substrate has the opening portions inside the opening portion of the first conductor layer, multiple electronic components positioned in the opening portions of the substrate, and an insulating layer formed on the substrate such that the insulating layer is formed on the electronic components and on the first conductor layer. The opening portions are formed in the substrate such that the opening portions include two opening portions and that the substrate has a partition wall formed between the two opening portions.