Labour wins Wakefield by-election
The result means Labour holds the seat, following the resignation of Clive Hudson last month.
Coun Hemingway was elected after gaining 1,353 votes - a majority of 506.
He said: "I'm thrilled to have been elected and was delighted with the result.
"It was a really good campaign and it was a good contest and a fair one.
"I want to thank the people of Stanley and Outwood for voting for me and also the Labour supporters who were brilliant.
"I want to focus on trying to make improvements to the road networks locally.
"I also want to work on boosting funding for local community groups if possible."
Coun Hemingway, 28, was previously a ward councillor for Horbury and South Ossett, and is a regional trade union official for Unison
His nearest challenger for last night's by-election was Nathan Garbutt Moore (Conservatives) who received 847 votes.
Nicola Sinclair (Lib Dems) got 165 votes, Lucy Brown (The Yorkshire Party) secured 153 votes and James Johnston (UKIP) received 136 votes.
The voter turnout at the by-election was 21.5 per cent.
Mr Hudson was first elected to the Stanley and Altofts ward, as it was known then, in 2000.
But he cited his work commitments as the catalyst for his decision to give up his seat.