A simple phenomenological formula for description of \alpha -decay half-lives T_\alpha of heavy (above ²⁰⁸Pb) and superheavy nuclei is proposed. The formula, expressing T_\alpha as a function of the decay energy Q_\alpha , has five adjustable parameters: three to describe even--even nuclei and two for accounting for effects of an odd proton and an odd neutron. The formula allows one to describe measured values of T_\alpha of 61 even--even nuclei roughly within a factor of 1.3, 45 odd--even nuclei within a factor of 2.1, 55 even--odd nuclei within a factor of 3.2 and 40 odd--odd nuclei within a factor of 4.0, on the average, when measured values of Q_\alpha are taken. Results of its use are compared with those of other formulae. Effects of various changes in the formula are discussed.

PACS numbers: 23.60.+e, 27.80.+w, 27.90.+b