A press release issued by the Belgian Federal Prosecutor's office said the operations targeted only individuals who partook in terrorists actions of PKK or supported them.
The operation which was launched and supervised by an interrogating judge in the cities of Brussels, Liege and Verviers was carried out in the scope of combat on terrorism.
Documents and computers were also seized in the raids by some 100 members of the country's anti-terror unit and local police in Brussels, Verviers and Gemmenich.
The Federal Prosecutor's office launched raids to residences and meeting venues of PKK supporters in Verviers region seeking for "concrete evidence".
The Luxembourg-based Court of First Instance said on Thursday that decisions made by EU governments in 2002 and 2004 to blacklist the two groups and freeze their assets were illegal under EU law. But both the EU and Turkey said the ruling was based on procedural grounds, and will not have any practical effects.
Turkish officials have repeatedly urged the Belgian authorities to take concrete steps against terrorist organization PKK in various platforms.
Turkey's Deputy PM Cemil Cicek had expressed Turkey's expectations from Belgium to take action against PKK at an international conference on security in Belgium in March.
"Turkey feels really uncomfortable about the activities of the terrorist organization PKK, which is on the list of EU's terrorist groups. Belgium is an EU country and Turkey is concerned about developments that would encourage terrorism," Cicek was quoted as saying.