We propose a lateral effective potential which allows a straightforward calculation of electron and hole states in V-groove quantum wires. This effective potential is used together with a suitable coordinate transformation which results in two decoupled one-dimensional Schrödinger equations which are readily solved. The energy levels and wave functions calculated by this method are in close agreement with several previous results, which indicates that this method may be valuable for the study of physical properties in V-shaped quantum wires which require analytically calculated wave functions. Also, the proposed effective potential gives rise to a shallow vertical quantum well which is found in some V-groove quantum wire structures.