IN THE LAST DECADE, THE NUMBER OF SEISMIC STATIONS HAS INCREASED SIGNIFICANTLY, AND NEW DENSER REGIONAL NETWORKS WITH ADVANCED TECHNOLOGY HAVE BEEN INSTALLED WORLDWIDE. MOREOVER, THE RECENT IMPROVEMENTS IN THE QUALITY OF SEISMOLOGICAL INSTRUMENTS HAVE RESULTED IN THE APPLICATION OF MODERN BROADBAND SEISMOMETERS WITH HIGH DYNAMIC RANGE DIGITIZERS FOR MOST SEISMOLOGICAL STUDIES. AMONG VARIOUS SEISMIC DATA, BROADBAND NETWORKS PROVIDE VALUABLE DATA FOR SEISMOLOGICAL RESEARCH. THE PURPOSE OF THIS RESEARCH IS TO SURVEY THE QUALITY OF CHABAHAR BROADBAND SEISMIC STATION RECORDS AND STUDY THE SITE EFFECT BY RECORDING THE EARTHQUAKES IN IRANIAN NATIONAL BROADBAND SEISMIC NETWORK RELATED TO INTERNATIONAL INSTITUTE OF EARTHQUAKE ENGINEERING AND SEISMOLOGY (IIEES) BY USING 111 RECORDS. IN THIS STUDY, THE Error-Rate OF THE STATION BY 8 EARTHQUAKES SELECTED WAS RECOGNIZED AND IN ORDER TO IDENTIFY SIGNAL-TO-NOISE RATIO IN A SINGLE EARTHQUAKE WAS CARRIED OUT. TO DETERMINE THE SITE EFFECT, THE METHOD OF H/V WAS USED. IN THIS METHOD, IT IS SUPPOSED THAT THIS SITE IS MADE OF ROCK AND SO IT HAS BEEN RESEARCHED IN ORDER TO FIND THE APPROXIMATE CAUSES OF Error-Rate. THEN, TO SHOW THE BACKGROUND-NOISE ON THE SITE, POWER SPECTRAL DENSITY CURVE WAS PLOTTED AND FINALLY A COMPARISON BASED ON NOISES AND THE SITE EFFECT IN CHABAHAR STATION TO THE OTHER IRANIAN BROADBAND SEISMIC STATIONS WAS MADE.