[en] Highlights: • We considered a non-minimal coupling inflationary model in the context of the constant-roll idea which was investigated by the first-order formalism. • We attempted to find the hidden symmetries behind the model by the Lie symmetry method. • We supplied this aim using the symmetry features of the Heun function. • We showed that the hidden symmetries of the nonminimal constant-roll inflation in the cases of power-law and exponential couplings are characterized as a generalized form of $sl(2,R)$ and $su(1,1)$ algebra, respectively. In the present work, we consider the non-minimal coupling inflationary model in the context of the constant-roll idea which is investigated by the first-order formalism. We attempt to find the hidden symmetries behind the model by the Lie symmetry method. We supply this aim by using the symmetry features of the Heun function instead of Killing vector approach. We show that the hidden symmetries of the non-minimal constant-roll inflation in the cases of power-law and exponential couplings are characterized as a generalized form of $sl(2,R)$ and $su(1,1)$ algebra,