An adjustable holding frame mainly includes a first bar, a second bar and an adjusting means. The second bar has one end fastened to a lump element which is pivotally located in the adjusting means. The adjusting means is mounted onto the first bar and has a helical structure to adjust the position of a seat in the adjusting means. Thereby releasing or fastening of the lump element of the second bar can be controlled to adjust the posture condition of the holding frame.