Am Basteir (Gaelic Am Baisteir, pronounced [əmˈpaʃtʲɛɾʲ]) is a mountain in the northern Cuillin range on the Isle of Skye in Scotland. It is 934 metres (3064 feet) high and classed as a Munro. It forms a narrow blade of rock, which bears comparison with the Inaccessible Pinnacle.
The easiest route to the summit starts from Sligachan following a path along the left bank of the Allt Dearg Beag (small red burn) for 5 km (3 miles) to a small lochan in the Coire a' Bhasteir, then up a gruelling scree slope to the bealach on the main ridge. A scramble of approximately 200 metres along the east ridge will bring you to the summit although care should be taken near the top as there is a "bad step", a 3 metre high notch in the ridge to negotiate. This could be scrambled down until recently but a rockfall now means it must be avoided, downclimbed or abseiled. The western side of Am Basteir is vertical, though it is possible for a walker coming from the direction of Bruach na Frìthe to reach the top by skirting below Am Basteir to reach the bealach mentioned above.
At the foot of the western side there is large prominent rock, similar in shape to Am Basteir itself, known as the Basteir Tooth.