Metal halide perovskites are promising for direct X-ray detection applications thanks to their high X-ray absorption capability and excellent charge carrier transport. Single-pixelated perovskite Xray detectors have hitherto demonstrated excellent device performance, including high sensitivity and detectivity. On the other hand, multipixel flat-panel detectors (FPDs) that enable 2D X-ray imaging are undeveloped due to challenges in scalable deposition processes. In this perspective, we summarize promising scalable perovskite deposition processes and discuss the challenges and opportunities toward direct X-ray FPD applications.