Spark energy is one of the most important parameters for SI engine, so it need be controlled effectively. Two modes of spark energy measurement were introduced in this paper: simulation load and direction measurement. 4 kinds of simulation load can be found: spherical discharger, three-pole discharger, Zener discharger and Zener string discharger, each has its own character. Zener string was chosen for it suited to electronic-controlled automotive engine. 2 kinds of direction measurement were introduced: attemperator, voltage and current sensor, the later was adopted for it can be realized easily and its precision characteristic. The test results show that the spark energy can be measured quantitatively and effectively in both modes; and the calculated spark energy of simulation load is larger than direction measurement for its less loss at the ignition circuit.