<p>In this paper, we provide two new methods of constructing entanglement-assisted quantum error-correcting (EAQEC) codes by using the LCD codes decomposition of linear codes. We first construct a class of maximal entanglement EAQEC maximum distance separable codes via the LCD codes decomposition of generalized Reed–Solomon (GRS) codes over finite fields <InlineEquation ID="IEq1"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="11128_2024_4630_Article_IEq1.gif" Format="GIF" Height="16" Rendition="HTML" Resolution="72" Type="Linedraw" Width="27" /> </InlineMediaObject> <EquationSource Format="TEX">\(\mathbb {F}_{2^m}\)</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi mathvariant="double-struck">F</mi> <msup> <mn>2</mn> <mi>m</mi> </msup> </msub> </math></EquationSource> </InlineEquation>. We then construct two classes of maximal entanglement EAQEC codes based on the LCD codes decomposition of matrix-product codes related to cyclic codes over finite fields <InlineEquation ID="IEq2"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="11128_2024_4630_Article_IEq2.gif" Format="GIF" Height="19" Rendition="HTML" Resolution="72" Type="Linedraw" Width="18" /> </InlineMediaObject> <EquationSource Format="TEX">\(\mathbb {F}_{q}\)</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi mathvariant="double-struck">F</mi> <mi>q</mi> </msub> </math></EquationSource> </InlineEquation>. In addition, we construct EAQEC codes with better parameters than the ones available in the literature.</p>