The application of conventional absorbing materials is limited due to complex preparation process andpoor transparency caused by fillers. In this study, a highly transparent ionic organogel was preparedby photocuring a dimethyl sulfoxide (DMSO) solution of a polymerizable magnetic cationic monomer[DAC]5[Dy(NCS)8]. Both components of organogel, which are the photopolymerizable magnetic cationicmonomer and polar solvent DMSO, have an important effect on the magnetic losses and dielectric lossesproperties of the organogel respectively. By tuning the mass ratio of DMSO to the monomer and the contentof the cross-linker, the complex permittivity of the gel could be effectively adjusted to improve theimpedance matching, and finally a gel with excellent wave absorption properties and good tensile propertieswas obtained. The optimum organogel was fabricated with a minimum reflection loss of 45.9 dBand a broadest effective absorption bandwidth (EAB) of up to 5.2 GHz, and effective absorption in the millimeterband (26.5–40 GHz) which is within the fifth generation (5G) mobile networks. With the advantagesof simple preparation method, arbitrary shape and good adhesion to a variety of substrates andcomplex surfaces, this multifunctional gel provides a new solution for complex scenarios requiring opticaltransparency and simultaneous absorption of electromagnetic waves.