F0 reset has been studied by researchers advocating differing theories regarding F0 downward trend in the course of utterances, and the definition of F0 reset depends heavily on their theoretical assumptions (Ladd [1]). In the declination theory, F0 reset is considered to be an upward shift of the global declination line, whether it is defined as a peak-to-peak "topline" or a valley-to-valley "baseline". In the downstep theory, by contrast, F0 is considered to be reset when downsteps of accented syllables are blocked. This paper investigates the F0 reset phenomenon using naturally-read texts in Japanese; auditorily determining F0 reset locations and acoustically characterizing this perception. The results indicate that the F0 rise between the preboundary low value and the postboundary peak value is the most consistent with the perception of F0 reset location.