A two-dimensional dosimetry system was developed for the quality assurance (QA) of therapeuticscanned ion beams at Heavy Ion Medical Accelerator in Chiba (HIMAC). This system consists of afluorescent screen and a charge-coupled device (CCD) camera. To evaluate the performance of thissystem, we carried out a few experiments concerning QA procedures. A verification of this systemwas also carried out by comparing the film dosimetry and the ionization chamber array. Also, weverified several types of corrections for errors, e.g., background and vignetting, that distort themeasurement results. As a result, we confirmed that this system could be used for QA proceduresof the therapeutic scanned ion beams.