QUANTITATIVE SCIENCE IS A BASIC COURSE FOR MASTER STUDENTS WHO HAVE BEEN ADMITTED TO DIVISION OF BIOSTATISTICS, INSTITUTE OF EPIDEMIOLOGY THROUGH PART-TIME-BASED TRACK. THIS COURSE IS PARTICULARLY USEFUL FOR THOSE WHO ARE LACKING OF STATISTICAL OR MATHEMATICAL BACKGROUND BEFORE THEY ARE ENTERTAINED BY FORMAL STATISTICS. THE COURSE STARTS FROM THE REVIEW OF BASIC CALCULUS, PROBABILITY THEORY, LINEAR MATRIX ALGEBRA, AND OTHER ADVANCED TOPICS SUCH AS DIFFERENTIAL EQUATION. A SERIES OF LECTURES ON THE APPLICATION OF SEVERAL IMPORTANT MATHEMATICAL THEOREM TO STATISTICAL ESTIMATION AND WILL BE GIVEN. THESE INCLUDE THE LINKAGE BETWEEN ORTHOGONAL PROPERTY AND INDEPENDENCE, THE ILLUMINATION OF SCORE FUNCTION IN RELATION TO FIRST DERIVATIVE, THE LIKELIHOOD FUNCTION AND MAXIMUM LIKELIHOOD ESTIMATE, TAYLOR SERIES FOR VARIANCE ESTIMATION, AND SIMPSON RULES FOR SAMPLE SIZE ESTIMATION IN SURVIVAL STUDIES. PRACTICAL EXAMPLES ON THESE TOPICS WILL BE DESIGNED AND PRACTICED BY STUDENTS DURING THE COURSE.