A pseudo-Riemannian Lie group (G, <., .>) is a connected and simply connected Lie group with a left-invariant pseudo-Riemannian metric of type (p, q). This paper is to study pseudo-Riemannian Lie groups with non-Killing conformal vector fields induced by derivations which is an extension from non-Killing left-invariant conformal vector fields. First we prove that a Riemannian (i.e. type (n, 0)), Lorentzian (i.e. type (n - 1, 1)) or trans-Lorentzian (i.e. type (n - 2, 2)) Lie group with such a vector field is solvable. Then we construct non-solvable unimodular pseudo-Riemannian Lie groups with such vector fields for any min(p, q) >= 3. Finally, we give the classification for the Riemannian and Lorentzian cases. (C) 2021 Elsevier Inc. All rights reserved.