In a joint press conference with German Chancellor Angela Merkel in Berlin Wednesday, the emir admitted that "mistakes" had been made, when asked about criticism from NGOs, unions and international organisations regarding the issue.
He said that many steps have been taken and several projects have yet to be implemented to enhance the situation of foreign workers.
Merkel said the subject had also been discussed during her meeting with Sheikh Tamim.
Germany defends good conditions for all workers in rich countries, Merkel said, adding that the emir had assured her he would react to international criticism.
Qatar last May announced a batch of reforms related to labour, including the controversial "Sponsor System", which bans foreign workers from leaving the country without the sponsor's permission. Most of these workers come from Asian countries.
Reports by organisations such as Amnesty International have condemned injustice and the exploitation of foreign workers in the 2022 World Cup projects.
This criticism led FIFA, the world soccer governing body, to demand better working conditions urgently.
The Guardian daily last year published a report by a Nepalese NGO which revealed the death of around 400 Nepalese workers in Qatar.
Qatar is home to around 420,000 expatriate Indians, a large number of whom are blue collar workers employed by construction companies.