He got more votes than Jack Rabbit, a Beagle, and Poppy, a Golden Retriever.
With almost 102 million Americans voting early and millions more waiting in lines on election day, the rancorous campaign across a polarised nation clearly struck a nerve with the electorate.
Only one country in the world has implemented an online voting system for its entire electorate: Estonia.
But incumbent Alpha Conde, seeking a controversial third term, has condemned Diallo's declaration as "irresponsible and dangerous".
The embattled president is the third to be toppled by popular uprisings in the former Soviet country since 2005.
In Sunday's local elections Ion Aliman won a landslide victory in Deveselu, Romania, despite having died the week before.
Germany's Greens won several mayoral races in North Rhine-Westphalia, the country's most populous state.