The case was, which manages copyrights for Belgium's French- and German-language newspapers and has stop displaying Belgian press reports.
Copiepresse argues that versions of news articles stored on Google can be seen on its service even after the articles are no longer freely accessible on a newspaper's Web site.
Google has faced a similar complaint in the United States from Agence France Presse. The French news agency filed a suit in 2005.
The Belgian court on Tuesday upheld an existing injunction, although reduced the penalty that Google would face if it chose to publish material from a variety of Belgian French- and German-language newspapers.
Following a ruling in September, Google faced a potential fine of $1.3 million (1 million euros) per day for reproducing articles and was also forced to publish the judgment or pay a further $650,000 per day.
The court on Tuesday cut the potential fine to $32,500 per day.
Google said it was disappointed with the ruling and that it planned an appeal.
Margaret Boribon, secretary-general of Copiepresse, told Reuters she was pleased with Tuesday's judgment, although expressed surprise that the potential fine had been cut.
She added that Copiepresse would still consider allowing Google to display extracts from the Belgian newspapers for a fee, although said it was up to Google to initiate contact.
"The initial purpose was to have a fair agreement," she said.