The representatives of a group calling itself People's Movement for a Just Society who met with the premier said the three major problems have been pending for years without solutions or signs of progress.
Another 100 activists with banners and loudspeakers demonstrated at a side entrance to Government House.
Yingluck said she has set up working committees to resolve the problems, admitting that some of the issues - particularly land disputes - involved law enforcement. She said more discussions on the issues are needed. The activists urged the premier to chair the working committees, saying the people continue to face major problems.
They cited the issuance of community land title deeds as one the most crucial issues.