As a quasi-one-dimensional spin frustrated material, Ca ₃Co ₂O ₆has a series of interesting physical properties such as low-temperature spin freezing and multiple magnetized steps due to its unique structure. The magnetic properties of Ca ₃Co ₂O ₆mainly come from Co ions, and the doping of different elements at the Co site has a great effect on the magnetic structure of Ca ₃Co ₂O ₆. At present, the magnetic research of Ca ₃Co ₂O ₆and its related compounds mainly focuses on exploring the influence of other elements replacing Co sites. For example, non-magnetic Sc ³⁺can dilute the intrachain ferromagnetic exchange, while the doping of magnetic ions Mn ⁴⁺, Fe ³⁺or Cr ³⁺can inhibit the intrachain ferromagnetic interaction and enhance the antiferromagnetic interchain interaction. Doping Ti ⁴⁺ions, which are high-valence non-magnetic ions, not only dilutes the magnetic interaction of Ca ₃Co ₂O ₆, but also changes the valence state of cobalt ions. i.e. it can convert part of Co ³⁺ions into Co ²⁺ions. Therefore, comparing with other doped ions, their introduction may have a more significant effect on the magnetoelectric properties of Ca ₃Co ₂O ₆. In this study, a series of Ca ₃Co _2–xTi _xO ₆( x= 0, 0.02, 0.04, 0.06) polycrystalline samples is prepared by sol-gel method. Their magnetic, dielectric and magnetodielectric properties are measured. The XRD patterns show that a small number of Ti ⁴⁺ions do not change the crystal structure of Ca ₃Co ₂O ₆. Due to the destruction of the long-range ferromagnetic correlation of Ca ₃Co ₂O ₆by non-magnetic Ti ⁴⁺ions, the ferromagnetic interaction is inhibited to some extent. Because Ti ⁴⁺ions are non-magnetic ions, they cannot form antiferromagnetic coupling with Co ions, resulting in the decrease of the Curie-Weiss temperature( θ). The positive θvalue and exchange constant still indicate that the ferromagnetic interaction is dominant in Ti ⁴⁺doped Ca ₃Co _2–xTi _xO ₆( x= 0, 0.02, 0.04, 0.06) samples. The substitution of non-magnetic ions Ti ⁴⁺for Co ³⁺ions also makes the effective magnetic moment of Ca ₃Co _2–xTi _xO ₆( x= 0, 0.02, 0.04, 0.06) monotonically decrease from μ _eff= 5.42 μ _Bfor x= 0 to μ _eff= 5.18 μ _Bfor x= 0.06. Accompanying the introduction of Ti ⁴⁺ions, the spin frustration of Ca ₃Co ₂O ₆is released partly, thus gradually fading the magnetization steps of Ca ₃Co ₂O ₆. As the Ca ₃Co ₂O ₆is a typical magnetodielectric material, the released spin frustration in Ti ⁴⁺doped samples and the variation of the subtle magnetic structure exert a large influence on the magnetodielectric coupling effect of Ca ₃Co _2–xTi _xO ₆( x= 0, 0.02, 0.04, 0.06) compounds.