Moel Sych is a subsidiary summit of Cadair Berwyn in north east Wales. It is jointly the second highest summit in the Berwyn range along with Cadair Berwyn North Top.
The summit was often considered to be the highest summit in the Berwyns until Cadair Berwyn North Top, then known as Cadair Berwyn was found to be of the same height. Later on the OS discovered a new top in between the two, which was 3m higher at 830m. This top, now known as Cadair Berwyn, is listed as Cadair Berwyn New Top on the Nuttall list.
The summit has a cairn, and overlooks Llyn Lluncaws in the southern Cwm.