The influence of high pressure on the conductivity in the basal plane of the oxygen deficient HoBa2Cu3O7−δ single crystals is investigated. It is determined that the excess conductivity Δσ(T) in the HoBa2Cu3O7−δ single crystals over a wide temperature range (Tc < T < T*, where Tc is the critical temperature and T* represents the mean field temperature of the superconducting transition) obeys an exponential temperature dependence. The description of the excess conductivity with Δσ ~ (1 − T/T*)exp(Δ*ab/T) can be interpreted in terms of mean field theory. The temperature dependence pseudogap is satisfactorily described within the framework of the BCS–BEC crossover.