Indian Passport holder, working in Singapore need F visa for China.

You should apply for a China F visa from the China Visa Application Service Center at 22 Malacca Street,#09-00 Royal Brothers Building, Singapore with the documents as follow:
1. Original passport with at least two blank visa pages and over 6 months validity;
2. Completed China visa application form V2011A with a recently-taken passport photo stuck on & V2011B;
3. Invitation Letter of Duly Authorized Unit and Confirmation Letter of Invitation issued by the Chinese government department’ companies and social organizations authorized by the Chinese Foreign Ministry;
4. Round-trip airline tickets;
5. documents in SPR,WP,EP,STP,DP;

It usually takes 4 working days, but there are also express service and rush service for applicants who are under emergencies.