Context :

Aims : We attempt to determine the nature of the high energy emission of the radio galaxy 3C 111 , by distinguishing between the effects of the thermal and non-thermal processes .

Methods : We study the X-ray spectrum of 3C 111 between 0.4 keV and 200 keV , and its spectral energy distribution , using data from the Suzaku satellite combined with INTEGRAL , Swift/BAT data , and Fermi/LAT data .
We then model the overall spectral energy distribution by including radio and infrared data .

Results : The combined Suzaku , Swift and INTEGRAL data are represented by an absorbed exponentially cut-off power-law with reflection from neutral material with a photon index \Gamma = 1.68 \pm 0.03 , a high-energy cut-off E _ { \mathrm { cut } } = 227 _ { -67 } ^ { +143 } keV , a reflection component with R = 0.7 \pm 0.3 and a Gaussian component to account for the iron emission-line at 6.4 keV with an equivalent width of EW = 85 \pm 11 eV .
The X-ray spectrum appears dominated by thermal , Seyfert-like processes , but there are also indications of non-thermal processes .
The radio to \gamma -ray spectral energy distribution can be fit with a single-zone synchrotron-self Compton model , with no need for an additional thermal component .

Conclusions : We suggest a hybrid scenario to explain the broad-band emission , including a thermal component ( iron line , reflection ) that dominates in the X-ray regime and a non-thermal one to explain the spectral energy distribution .