In anterior cruciate ligament (ACL) deficient knee, several treatment methods were recommended. Recently, arthroscopic reconstruction is widely used as the best treatment method. As the graft materials, bone-patellar tendon-bone (BPB) unit is a gold standard material. Whereas, it has many problems. The purpose of this study was to introduce the new arthroscopic ACL reconstruction technique with quadrupled semitendinosus tendon and Endobutton and to evaluate its results. Twenty one patients were prospectively reviewed after ACL reconstruction with quadrupled semitendinosus tendon and Endobutton at one year post-operation. The surgery was performed in the series of graft tendon harvest, graft preparation, tunnel drilling and Endobutton fixation. The outcomes showed improved knee functions. Endobutton technique with quadrupled semitendinosus tendon is useful method for the arthroscopic ACL reconstruction. Stability and functional outcomes were similar to those with patellar tendon but it showed less donor site morbidity, less pitfall of fixation and simple procedure.