Purpose: The aim of the study was to investigate the image quality of dual-energy computed tomography angiography (DECTA) using the selec-tive photon shield (SPS) technique to diagnose intracranial aneurysms. Materials and Methods: Eighty patients with a suspected intracranial aneurysm were randomly assigned to undergo DECTA with SPS (ie, SPS-DECTA) or DECTA without SPS (ie, DECTA). The objective image quality of these 2 groups was compared with digital subtraction angiography and surgical results as the reference. The location, number, and morphology of the aneurysms were evaluated between the 2 groups. The display degree and the size of aneurysmal neck and the diameters (ie, long and short axis) of the aneurysm were compared between the 2 groups. Results: The signal-to-noise ratio and contrast-to-noise ratio of SPS-DECTA were significantly higher than those of DECTA (P < 0.05). The difference between the 2 groups in intracranial vascular subjective scoring was not statistically significant (P > 0.05). In 30 of the 40 patients in the SPS-DECTA group, an aneurysm was detected without misdiagnosis or missed diagnosis. The aneurysm location, aneurysm number, and measurements by the 2 methods were closely correlated without significant statistical differences (the R values were 0.953, 0.982, and 0.974, respectively; P = 0.000). The detection rate was 93% (26/28 patients). In the DECTA group, 2 patients were misdiagnosed. Mean long and short diameter and neck size by three-dimensional digital subtraction angiography were 5.82 +/- 3.27, 4.67 +/- 3.31, and 3.29 +/- 1.38 mm, respectively. Aneurysm locations, number, and neck size by the 2 methods were closely correlated without a significant statistical difference (R values were 0.964, 0.968, and 0.856, respectively; P = 0.000). Conclusions: The SPS-DECTA is very accurate for diagnosing intracranial aneurysms and could be a routine noninvasive screening method.