Nationals of the People's Republic of China with residency (hukou) in Mainland China (including those who are non-permanent residents of Hong Kong or Macau and have relinquished their hukou in Mainland China) require prior approvals from Taiwanese government and are required to hold an Exit and Entry Permit prior to travelling to Taiwan. As of August 2016, Mainland residents can only visit Taiwan as a part of a pre-approved tour group unless they qualify for one of the exemptions:

Can we conclude that do mainland chinese need a visa for taiwan?
yes