A sample preparation method includes: irradiating a first region of a sample with light at a time t1; irradiating a second region different from the first region with the tight at a time t2 after the time t1; and fixing the sample at a time t3 after the time t2. A sample preparing apparatus includes: a light radiating unit that irradiates a first region of a sample with light at time t1 and irradiates a second region different from the first region with the light at a time t2 after the time t1; and a fixing unit that fixes the sample at a time t3 after the time t2.