An apparatus and method for detecting bio molecule using an inductor element that can detect the bonding reaction between a sample and a biochip by measuring the change of the electrical characteristics of a circuit including the inductance device. The method includes forming a signal conversion unit with at least one inductance device, arranging a biochip in a specified area of the signal conversion unit by immobilizing capturing probe biomolecules on a substrate and measuring electric characteristics of the signal conversion unit, performing a bonding reaction between a sample (such as DNA, RNA, protein, biomolecules, etc.) to be analyzed and the biochip, and measuring the electrical characteristics of the signal conversion unit after the reaction bonding. The result of the bio molecule detection is obtained through an electrical signal, and thus the capability of detecting the bio bonding reaction can be improved in comparison to the conventional apparatus and method.