A prostate cancer diagnosis device using a fractal dimension value DF, comprising: a semiconductor laser emitting a laser beam; an endoscope transmitting the laser beam to a biopsy tissue in a human body and receiving auto-fluorescence generated from the biopsy tissue; an optical unit transmitting the laser beam to the endoscope and receiving an auto-fluorescence generated from the biopsy tissue from the endoscope; a detection unit detecting the auto-fluorescence received by the optical unit and measuring the intensity of the time-dependent autofluorescence in form of an auto-fluorescence measured value by a Time Correlation Single Photon method; and a diagnosis unit calculating DF- values of the auto-fluorescence measured value using a fractal dimension algorithm, wherein the fractal dimension algorithm comprises: when the auto-fluorescence measured value is I(t), selecting a maximum I(t) that is higher than a predetermined reference intensity Iref as a target; approximation modeling the selected I(t) to a linear value using a modeling function F(t); calculating a correlation function that indicates a difference obtained by subtracting a measured value of an attenuation period of I(t) from the maximum value Fmax of F(t); modeling the correlation function with a fractal model and then replacing the modeled correlation function with a log function; calculating a fractal dimension function corresponding to a slope of a curve represented by values of the log function, the slope being determined by a start time and a variable time length; while the variable time length is fixed with respect to the fractal dimension function dDF(tu, t), calculating a first fractal dimension function value by changing the start time and determining a first start time corresponding to the minimal value of the calculated first fractal dimension function value; and while the start time is fixed to the first start time with respect to the fractal dimension function, calculating a second fractal dimension function value by changing the variable time length and determining the minimal value of the calculated second fractal dimension function value as the fractal dimension value. a semiconductor laser emitting a laser beam; an endoscope transmitting the laser beam to a biopsy tissue in a human body and receiving auto-fluorescence generated from the biopsy tissue; an optical unit transmitting the laser beam to the endoscope and receiving an auto-fluorescence generated from the biopsy tissue from the endoscope; a detection unit detecting the auto-fluorescence received by the optical unit and measuring the intensity of the time-dependent autofluorescence in form of an auto-fluorescence measured value by a Time Correlation Single Photon method; and a diagnosis unit calculating DF- values of the auto-fluorescence measured value using a fractal dimension algorithm, wherein the fractal dimension algorithm comprises: when the auto-fluorescence measured value is I(t), selecting a maximum I(t) that is higher than a predetermined reference intensity Iref as a target; approximation modeling the selected I(t) to a linear value using a modeling function F(t); calculating a correlation function that indicates a difference obtained by subtracting a measured value of an attenuation period of I(t) from the maximum value Fmax of F(t); modeling the correlation function with a fractal model and then replacing the modeled correlation function with a log function; calculating a fractal dimension function corresponding to a slope of a curve represented by values of the log function, the slope being determined by a start time and a variable time length; while the variable time length is fixed with respect to the fractal dimension function dDF(tu, t), calculating a first fractal dimension function value by changing the start time and determining a first start time corresponding to the minimal value of the calculated first fractal dimension function value; and while the start time is fixed to the first start time with respect to the fractal dimension function, calculating a second fractal dimension function value by changing the variable time length and determining the minimal value of the calculated second fractal dimension function value as the fractal dimension value.