BEIJING - German firms in China are still optimistic about their local sales growth despite the economic slowdown, a report showed Tuesday.

About 90 percent of the surveyed 189 German firms, based in China, planned to continue business in China despite the economy seeing the weakest quarter-on-quarter expansion in the first quarter since 2011, according to the report released by the German Chamber of Commerce in China.

Over one third of the surveyed German firms have taken steps such as rolling out new products and services to adapt to market changes, the report showed.

Meanwhile, most German firms look forward to the opportunities brought about by China's development plan for the next five years. Over half of the surveyed firms regard China's growing sales market to be their biggest opportunity as more Chinese firms upgrade their systems and equipment.

"One important area of business we see from the 13th Five-Year Plan is the focus on innovation -- this carries the potential for ample Sino-German business cooperation," said Alexandra Voss, North China executive director with the German Chamber of Commerce in China.

China is Germany's largest trade partner outside Europe. There are more than 5,000 German companies in China. Sentiment is high among the firms as they have been encouraged by China's efforts in the areas of environmental protection and innovation, according to the report.

They also expected more agreeable market environment thanks to continuous opening up and easier market access, the report said.