More than 71% of civil servants surveyed oppose the plan, Nida Poll said on Sunday.
The survey also found that 58% of respondents strongly support a minimum salary of 25,000 baht per month for employees with a Bachelor's degree.
The nationwide survey was conducted from September 19-21 on 1,310 civil servants, employees, and state enterprise employees aged 18 and above.
The poll also asked those surveyed whether their salaries were adequate: 44.81% said their salaries were too low to cover expenses and savings were impossible, 28.32% said their salaries covered their expenses and allowed them to save, and 26.87% said their salaries covered their expenses but did not allow them to save.
Most respondents said they were in debt: 44.35% had debts with financial institutions, 43.36% had debts with cooperatives, and 3.66% had debts from other lenders.
When asked if they supported the plan to pay salaries twice a month:
71.30% - strongly disagreed
11.83% - disagreed
8.32% - strongly agreed
7.71% - somewhat agreed
0.84% - had no response.
When asked whether they support the plan to raise the minimum monthly salary for degree holders to 25,000 baht a month:
57.86% - strongly agreed
20.38% - somewhat agreed
13.36% - strongly disagreed
7.94% - disagreed
0.46% - had no response.