The gas-rich emirate has been slapped with sanctions and demands after four countries including regional kingpin Saudi Arabia cut ties with it on June 5, accusing Doha of fostering "terrorist" groups and of links to Riyadh's arch-rival Iran. Qatar denies the allegations.
The Ministry of Economy and Commerce said a complaint had been lodged with the WTO's Dispute Settlement Body against the "siege countries."
According to the emirate, Saudi Arabia, the United Arab Emirates and Bahrain are violating laws and conventions related to trade.
The Saudi-led bloc has demanded the termination of regional news giant Al-Jazeera, the downgrading of Iran ties and the closure of a Turkish military base in the country.
The countries have also recalled their ambassadors from Doha, ordered all Qataris to return home and banned Qatar from using their airspace.
"The complaint accuses the siege countries of violating the WTO's core laws and conventions on trade of goods and services, and trade-related aspects of intellectual property," the Qatar ministry said.
"The arbitrary measures taken by the siege countries are a clear violation of the provisions and conventions of international trade law.
"Furthermore, the illegal siege is unprecedented in the framework of economic blocs," Qatar's economic and commerce minister Sheikh Ahmed bin Jassem bin Mohammed Al-Thani said in the statement.
The diplomatic crisis between Doha and its neighbours is the biggest to have hit the Gulf Cooperation Council in decades.
The isolation campaign has forced Qatar to seek more expensive imports and reroute flights on costly detours over friendlier airspace.