Teodoro Mariani (28 February 1882 – 2 August 1916) was an Italian rower.

He received his education at Caio Plinio Secondo in Como from which he graduated in 1900 with a major in accounting.

At the 1911 European Rowing Championships in his home town Como, he became European champion in double sculls teamed up with Giuseppe Sinigaglia who he had been friends with from his time at ASDG Comense 1872.

He was killed by shrapnel on 2 August 1916 fighting on Monte Zebio.

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