As a quasi-one-dimensional spin frustrated material, Ca ₃Co ₂O ₆has a series of interesting physical properties due to its unique structure, such as low temperature spin freezing, multiple magnetized steps. 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 the related compounds is mainly on exploring the influence of other elements replacement at Co sites. For example, non-magnetic Sc ³⁺can dilute the intrachain ferromagnetic exchange, while magnetic ions Mn ⁴⁺, Fe ³⁺or Cr ³⁺doping can inhibit the intrachain ferromagnetic interaction and enhance the antiferromagnetic interchain interaction. As a high-valence non-magnetic ion, Ti ⁴⁺doping not only dilutes the magnetic interaction of Ca ₃Co ₂O ₆, but also changes the valence state of cobalt ions. I.e., it can change part of Co ³⁺to Co ²⁺. Therefore, comparing with other doped ions, its 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 were prepared by sol-gel method. Their magnetic, dielectric and magnetodielectric properties were measured. The XRD patterns show that a small amount of Ti ⁴⁺does not change the crystal structure of Ca ₃Co ₂O ₆. Due to the destruction of non-magnetic Ti ⁴⁺ions to the long-range ferromagnetic correlation of Ca ₃Co ₂O ₆, the ferromagnetic interaction is inhibited at some extend. However, due to Ti ⁴⁺ions are non-magnetic ions, it cannot form antiferromagnetic coupling with Co ions. It only results 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= 5.42μ _Bfor x= 0 to μ_eff= 5.18μ _Bfor x= 0.06. Accompanying the introduction of Ti ⁴⁺ion, the spin frustration of Ca ₃Co ₂O ₆is released partly. The magnetization steps of Ca ₃Co ₂O ₆thus fade gradually. 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 present a large influence on the magnetodielectric coupling effect of Ca ₃Co _2-xTi _xO ₆( x= 0, 0.02, 0.04, 0.06) compounds.