Introduction: Mammography is the gold standard in breast cancer diagnosis, requiring periodic quality control tests to ensure the compliance of images and patient exposure doses with current protocols [1,2]. Some of these tests need specific physical simulators, which are expensive and not easily accessible. To address this, the International Atomic Energy Agency (IAEA) developed a simple phantom made from readily available materials for quality control in mammography. This phantom is designed for use with the ATIA software, which automates image analysis, DICOM data extraction, and the export of results to CSV files [3,4]. Objective: The objectives of this work were: (a) to manufacture the mammography phantom according to the standard mold recommended by the IAEA Human Health Series publication No. 39; (b) to acquire images in a digital mammography system of the fabricated simulator and a specific simulator for testing signal-to-noise ratio (SNR) and differential signal-to-noise ratio (SDNR); (c) to compare the objective metrics obtained from the phantoms using two quality control software programs. Methodology: A mammography phantom was fabricated, consisting of two parts. The first part comprises four uniformly attenuating PMMA plates, each measuring 24 x 30 x 1 cm. The second part includes a PMMA target plate measuring 24 x 30 x 0.5 cm, containing a square piece of copper (5 x 5 cm, 1 mm thick) and a piece of aluminum (1 x 1 cm, 0.2 mm thick) [3,4]. For preliminary validation, an image was acquired using the IAEA phantom in the MoMo target-filter configuration (28 kV, 63 mAs). This image was processed using ATIA software to verify the automatic positioning of regions of interest (ROIs). Subsequently, the image was analyzed using ImageJ software, where necessary ROIs were manually delineated, and the average pixel values and standard deviations were extracted. The second part of the validation uses the same methodology with the PIXMAM phantom from Leeds Test Objects, consisting of acrylic plates (24 x 30 x 4.5 cm) with an aluminum piece attached to the acrylic target plate [5]. This stage includes an inter-comparison of the results obtained with both phantoms. Results: Upon inserting the image into the ATIA software, the ROIs were correctly positioned automatically. The values obtained from ATIA for SDNR and SNR were 4.98 and 22.74, respectively. The values obtained from ImageJ for the same metrics were 20.25 for SDNR and 51.24 for SNR. Therefore, there is a difference between the results from the two software programs of approximately -15.27 for SDNR and -28.50 for SNR. Conclusions: It is concluded that the phantom was correctly recognized by the ATIA software. The preliminary results show a significant difference between the quality control software programs, which may be explained by the variability in the manual positioning of the ROIs in ImageJ. The second part of the validation is currently in progress. This work was supported by the Brazilian National Council for Scientific and Technological Development (CNPq, INCT/INAIS Project – 406303/2022-3; CNPq Process 308368/2022-3 – Productivity Grant; and CNPq Master's Scholarship), the Coordination for the Improvement of Higher Education Personnel (CAPES), and the State Agency for Research and Development of Minas Gerais (FAPEMIG).