"SA Pen has the impression that the new owner of Independent News and Media SA has not yet comprehended the treasured and universal concept of editorial independence," the organisation said in a statement.
The Pen is a non-political organisation representing writers globally.
Dasnois was dismissed on 6 December after the newspaper ran a story which painted its newspaper group shareholder Sekunjalo in a negative light.
The dismissal drew outcries, especially from media circles.
The story was about a finding by Public Protector Thuli Madonsela that the awarding of a tender by the agriculture, forestry, and fisheries department to Sekunjalo Marine Services Consortium was improper.
The consortium is a subsidiary of Sekunjalo Holdings and acquired a controlling share in Independent News and Media SA (INMSA) earlier this year.
Sekunjalo Investments subsequently sent a lawyer's letter to the Cape Times stating that the story was inaccurate.
Gasant Abarder was appointed editor in place of Dasnois.
The chairperson of INMSA, Iqbal Surve, has since denied that Dasnois was dismissed, and said she had been redeployed to another editorial position.
"The SA PEN aligns itself with any considered move to help restore the editorial independence of the Cape Times and the job security of journalists in the INMSA group," the organisation said.
It was reported that Dasnois has since sought legal advice.