Temperature and composition dependence of the dc resistivity (ρdc) and thermoelectric power (α) of Li0.3–0.5x Zn0.4Cax Fe2.3–0.5x O4 ferrites (x = 0.0, 0.01, 0.02, 0.03 and 0.05), prepared by the standard ceramic method, have been studied. The behavior of both ρdc and α with temperature support the electron hopping conduction mechanism in the ferrimagnetic phase while the band mechanism dominates in the paramagnetic phase. Moreover, it was found that both ρdc and α decrease with increasing x up to x = 0.02 and then increase. The frequency and composition dependence of ε ′, ε ″ and ρac are found to support Koops's model. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)