A foldable handheld device is disclosed, which includes a first casing, a second casing, a connecting mechanism for connecting the first casing to the second casing, and an elastic piece disposed on the first casing. The second casing has a support surface and a curved surface connecting to the support surface, wherein the curved surface has a concave portion. An end of the elastic piece has a protrusion disposed thereon, wherein the protrusion is kept touching the second casing when the second casing is rotated related to the first casing along a rotating axle.