OBJECTIVE. The purpose of our study was to compare the image quality of a wet laser printer with that of a paper printer for full-field digital mammography (FFDM). MATERIALS AND METHODS. For both a wet laser printer and a paper printer connected to an FFDM system, image quality parameters were evaluated using a standardized printer test image (luminance density, dynamic range). The delectability of standardized objects, on a phantom was also evaluated. Furthermore, 640 manmograms of 80 patients with different breast tissue composition patterns were imaged with both printers. Subjective image quality parameters (brightness, contrast, and detection of details of anatomic structures-that is. skin, subcutis, musculature, glandular tissue, and fat), the delectability of breast lesions (mass, calcifications), and the diagnostic performance according to the BI-RADS classification were evaluated, RESULTS. Both the luminance density and the dynamic range were superior for the wet laser printer. More standardized objects were visible on the phantom imaged with the wet laser printer than with the paper printer (13/16 vs 11/16). Each subjective image quality parameter of the mammograms from the wet laser printer was rated superior to those of the paper printer. Significantly more breast lesions were detected on the wet laser printer images than on the paper printer images (masses, 13 vs 10, calcifications, 65 vs 48. p < 0.05). With the paper printer images, BI-RADS 4 and 5 categories were underestimated for 10 (43.5%) of 23 patients. CONCLUSION. For FFDM, images obtained from a wet laser printer show superior objective and subjective image quality compared with a paper printer, As a consequence, the paper printer should not be used for FFDM.