"The ship was released today. The crew is fine," Kubilay Marangoz, a lawyer for the Istanbul-based YDC Maritime company, said.
Marangoz would not comment on how the release was secured, but he had said earlier that the company was negotiating a ransom with the pirates.
The vessel, Karagol, with a 14-man Turkish crew, was seized on November 12 off the coast of Yemen with a cargo of 4,500 tonnes of chemicals from Israel to India.
It was was the second Turkish ship to be released by Somali pirates in a week. A Turkish-operated cargo vessel hijacked in December remains in the pirates' hands.
Piracy is rife and well organised in the area where Somalia's northeastern tip juts into the Indian Ocean, preying on a key maritime route leading to the Suez Canal.
More than 130 ships were attacked in the area in 2008 alone.
The heavily armed pirates operate high-powered speedboats and sometimes hold ships for weeks before releasing them for large ransoms paid by governments or shipowners.
They are estimated to have raked in $120 million in ransom money last year.