Ninety percent of German companies in China are optimistic about China's development and plan to increase their investments over the next five years, according to a survey by the German Chamber of Commerce.

Results of the 2011 German Business in China: Business Confidence Survey were released Sept 30 in Beijing.

Over half of the surveyed German businesses plan to set up new branches or factories in China, according to the report.

About 43 percent of the surveyed companies said they plan to increase investment in 2011. Seventy-seven percent of the enterprises rank China as one of their top three priorities in their global investment plans, and a quarter said China is their top priority.

According to the survey, human resources are the main problem and will remain the biggest challenge in the future.

The confidence survey is held every year. This year, 188 member companies participated, accounting for 9.3 percent of the German chamber's member enterprises in China.