Provided is a layered double hydroxide membrane containing a layered double hydroxide represented by the formula: M2+1-xM3+x(OH)2An−x/n.mH2O (where M2+ represents a divalent cation, M3+ represents a trivalent cation, An− represents an n-valent anion, n is an integer of 1 or more, and x is 0.1 to 0.4), the layered double hydroxide membrane having water impermeability. The layered double hydroxide membrane includes a dense layer having water impermeability, and a non-flat surface structure that is rich in voids and/or protrusions and disposed on at least one side of the dense layer. The present invention provides an LDH membrane suitable for use as a solid electrolyte separator for a battery, the LDH membrane including a dense layer having water impermeability, and a specific structure disposed on at least one side of the dense layer and suitable for reducing the interfacial resistance between the LDH membrane and an electrolytic solution.