For an integer $p\geq 2$ we construct vertical and horizontal one-pth Riordan arrays from a Riordan array. When $p=2$, one-pth Riordan arrays reduced to well known half Riordan arrays. The generating functions of the $A$-sequences of vertical and horizontal one-pth Riordan arrays are found. The vertical and horizontal one-pth Riordan arrays provide an approach to construct many identities. They can also be used to verify some well known identities readily.