The aim of this study is to develop a new method to measure one-dimensional dose distribution of high-energy electron using a miniature fiber-optic radiation sensor. The measurements are made by a thin plastic optical fiber with an organic scintillating sensor tip. The scintillating light in the visible wavelength range is guided to a silicon photodiode by plastic optical fiber in order to convert light output to electrical signal. The one-dimensional spatial dependence of elctron beam is measured by moving the sensor tip with uniform speed. It is shown that this fiber-optic radiation sensor has better spatial resolution than conventional ion chamber and it needs much less time to measure one-dimensional dose distribution in the high radiation fields.