To provide a method of manufacturing an embedded form holder made of concrete, with good mass productivity in a short period of time under the conditions of room temperature and normal pressure without water curing, the form holder allowing any operator to easily achieve a uniform recessed face on a concrete structure, after pouring concrete, to thereby obtain high compressive strength of the concrete structure.

The embedded form holder is mainly made of concrete which is a mixture of a compound material containing a cement raw material of 100 wt.% and fine aggregate of 150 wt.%, and mixing water containing a water reducing admixture on the order of 1% of the weight of cement, added to the compound material beforehand, at a water-cement ratio of 42%. Then the embedded form holder is formed before the concrete is hardened such that a chamfering packing is stuck to a finish surface of the holder beforehand. The packing is of a sealing structure such as a double-faced sealing tape, so that one side of the tape is easily separable. Therefore the holder can secure a suitable gap with respect to the form, and only by separating the packing after the form is released, the uniform chamfered finishing is easily achieved by any operator.