To explore the feasibility and effect of microsurgical treatment of complex intracranial aneurysms via keyhole approaches. Operation via keyhole approach was performed on thirty-one patients with 42 complex intracranial aneurysms were operated on, including 2 internal carotid artery bifurcation aneurysms, 1 anterior cerebral artery aneurysm, 12 posterior communicating artery aneurysms, 2 anterior choroids artery aneurysms, 7 middle cerebral artery aneurysms, 6 anterior communicating artery aneurysms, 2 basilar artery aneurysms, 2 vertebral artery aneurysms, 4 posterior cerebral artery aneurysms and 4 ophthalmic artery aneurysms, among which were 10 cases with multiple intracranial aneurysms, 14 with giant aneurysms, and 7 with posterior circulation aneurysms, and 4 aneurysms clipped by drilling off anterior clinoid process. Six of the 31 patients who had giant aneurysms came to hospital because of the symptoms, such as dizziness, headache, oculomotor paralysis, loss of vision, etc, and the other 25 patients were grouped according to the subarachnoid hemorrhage (SAH) Grade: 5 in grade I, 12 in grade II, 7 in grade III and 1 in grade IV. Eight patients were operated on after SAH in the early-phase, while 8 in the middle-phase and 9 in the late-phase. The supraorbital subfrontal keyhole approach was used 25 times, the pterional approach 5 times, the subtemporal approach 3 times, and both the suboccipital lateral approach and the retromastoid approach once. 31 of the 42 aneurysms were clipped, 2 mini-aneurysms wrapped, 5 giant aneurysms clipped and resected, 2 aneurysms trapped with thrombotic aneurysm partially resected, 1 aneurysm trapped, while 1 ruptured before operation and untreated. Short-term Glasgow outcome scoring showed good recovery in 27 patients, moderate disability in 2, and death in 2. Operation via keyhole approaches effectively controls the immature rupture of intracranial aneurysm, removes anterior clinoid process, respects giant aneurysm, and reconstructs the parent artery of wide-neck aneurysm. Based on individualized surgical approaches and excellent microsurgical skills, the complex intracranial aneurysms can be treated safely, directly and effectively via minimally invasive keyhole approaches.