The invention discloses a transformer iron core. The transformer iron core comprises an upper iron core end ring and a lower iron core end ring in butt joint; the butt edge of the upper iron core endring is provided with at least two upper iron core butt bars which are symmetrically arrange, the butt edge of the lower iron core end ring is provided with a plurality of lower iron core butt bars corresponding to the upper iron core butt bars, at least one support iron core bar is arranged between the upper iron core butt bars and the lower iron core butt bars which correspond to each other, andgas gaps are formed between the support iron core bars and the iron core butt bars and filled with protective layers. The gas gaps formed between the support iron core bars and the iron core butt bars can avoid magnetic saturation of the iron core during operation; the gas gaps are filled with the protective layers to ensure rigidity of the iron core and safe operation of a transformer and to prolong the service life of the iron core. The invention also discloses the transformer comprising the transformer iron core.