Abstract: An adjustable hair piece includes a hair fixing band, a plurality of hair strands, a first detachable attaching portion, a pair of second detachable attaching portions, and one or two hair-fixing portions. The hair fixing band has a bottom surface and a top surface. The first detachable attaching portion is provided on the top surface of the hair fixing band. The pair of second detachable attaching portions are for being attached detachably to corresponding portions of the first detachable attaching portion. The one or two hair-fixing portions are connected to the pair of second detachable attaching portions and fix the adjustable hair piece to user's hairs. The pair of the second detachable attaching portions are detachably attached and fixed to the corresponding portions of the first detachable attaching portion with an adjustable length between the second detachable attaching portions. The hair-fixing portion may include an adjustable string or fine-toothed combs.