Provided is a method of isolating a nucleic acid from a microorganism cell using a nonplanar solid substrate, a method of amplifying a nucleic acid using the isolated nucleic acid as a template, and a device including the nonplanar solid substrate for isolating and amplifying a nucleic acid. The method of isolating includes contacting a nonplanar solid substrate with a cell-containing sample in a liquid medium having a pH of 3.0 to 6.0 thereby binding cells to the nonplanar solid substrate, and lysing the cell bound to the nonplanar solid substrate. The device comprises a reaction chamber comprising a nonplanar solid substrate a heating unit for heating the reaction chamber and a temperature-controlling unit for controlling the heating unit.
