To prevent peeling between a master substrate and a resin layer such as a resin sheet by improving bondability between the master substrate and the resin sheet.

A method of manufacturing the resin-sealed electronic component includes: a first step of preparing a master substrate 10 including a slave substrate region 11 formed by putting together a plurality of slave substrates and margin regions 12 provided around the slave substrate region 11, and preparing the master substrate 10 having recognition marks 24 on the margin region 12; a second step of mounting surface-mounting components on the slave substrate region 11; a third step of providing a half-cured resin layer 60 so as to cover the surface-mounting electronic components; a fourth step of curing the resin layer 60; and a fifth step of dividing the master substrate 10 on the basis of the recognition marks 24 and taking out the slave substrate having surface-mounting components which are sealed with a resin. In the second step, protrusions 40 are provided more closer to the slave substrate region 11 than to the recognition marks 24 in the margin regions 12, and in the third step, the resin layer 60 is provided so as to also cover the protrusions 40.