Lithium-substituted ferrites due to a good combination of magneto-dielectric properties are excellent materials for use in such devices as gas sensors, various devices of microwave electronics, for example in phase shifters, switches, etc. [1-2]. Most of electromagnetic properties of ferrites are structurally-sensitive, i.e. the magnetic state of the substance and the dynamics of the magnetization reversal processes are specified by both the chemical composition of the material and the content of microstructure defects. An initial permeability, μi, a coercive force, Hc are the most important static magnetic characteristics of ferrite ceramics. These characteristics have high structural sensitivity, good theoretical binding to certain defectiveness parameters and, therefore, can be used as indicators of the defect state and the phase composition of the ferrite material. In this work, the influence of sintering regimes on the microstructure (the grain size, density and porosity), saturation magnetization, the Curie point and the temperature dependence of the initial permeability of LiTiZn ferrite ceramics, was investigated. Ceramics was prepared by a standard ceramic technique. The formation of a single-phase cubic spinel structure was confirmed by XRD analysis. The Curie point was determined from both the temperature dependences of the initial permeability and the method of thermogravimetric measurements in a magnetic field. The results showed that the density / porosity and the grain size are sensitive to the sintering regime, while the Curie temperature and magnetization are independent of it. The results obtained from the temperature dependence of μi showed that for all LiTiZn ferrite samples there is a sharp decrease of μi near the Curie point. This behavior assumes the formation of a single-phase and chemically homogeneous ferrite structure. The initial permeability of ferrite decreases with increasing of sintering temperature (in the range (1010–1150) °С) and grain size, which contradicts the generally accepted Globus and Smith and Wijn theories. A possible reason for this behavior is the formation of intragranular pores growing with increasing of sintering temperature, which inhibit the domain wall motion inside the grain. These results correspond to the porosity of the investigated ferrite ceramic samples, which grows with sintering temperature increasing. In addition, deterioration of ceramics microstructure due to an increase in grain size dispersion affected the decrease of ferrite initial permeability. Thus, maximum value of the dependence μi (T) can be used as an indicator of the structure perfection or the level of defect state. For the studied ferrite samples, the sintering regime of 1010 °С 2 h proved to be optimal from the point of view high density and low porosity, the highest maximum value of the dependence μi (T) and therefore low level of defect state.