President John Magufuli, the ruling Chama Cha Mapinduzi flagbearer, cast his vote on Wednesday morning as polls continued on both Tanzania's mainland and semi-autonomous Zanzibar islands.
Dr Magufuli, who is seeking re-election, voted at Chamwino in Dodoma near State House where he is registered.
He arrived at the Chamwino Ikulu village with his wife, Janet Magufuli, and queued behind other voters who had lined up at the polling station.
After voting, Dr Magufuli briefly spoke to journalists, saying he was satisfied with the ongoing process.
"Congratulations to the returning officers for the preparations. I congratulate Tanzanians for this important day. My call is for them to hugely turnout and vote for the candidates of their choice," he said.
"We also need to maintain our peace and I always say there is life after elections."
He then displayed his inked finger to confirm that he voted.
Dr Magufuli turned down requests to answer more questions during the media briefing.
Over 29 million Tanzanians were registered to vote in the polls which involve 15 presidential candidates.
Polling stations were opened in the morning and voting continues to 4pm in the evening.
-Report by Alawi Masare