A study conducted for the newspaper Schweiz am Sonntag found just 23 percent supported the pension age proposal made by a parliamentary commission.
It comes as parliament prepares to debate pension reform.
The findings are in line with previous surveys which have found opposition to the retirement age being raised to 67 from 64 for women and 65 for men.
The latest study conducted in German and French-speaking Switzerland also sounded out opinion ahead of a nationwide vote on the AHV on September 25th.
It found 34 percent planning to vote yes to the ‘AHV plus' initiative, with 25 percent voting no and 41 percent still undecided with just two weeks to go until polling.
The initiative led by the trade union federation SGB/USS calls for old-age pensions to be increased by 10 percent.
The increase would cost 4.1 billion francs per year and be financed from higher salary deductions.
Meanwhile, organizers say 20,000 people took part in a demonstration in Bern at the weekend for a strong AHV.
An alliance of centre-left-Green parties, and employee and pensioner associations called the demonstration to oppose the parliamentary commission's recommendation for an automatic increase in the pension age.
Parliament still has to decide on the recommendation made in August by the National Council commission for social security and health.
The pension scheme reform will be debated in the National Council during the autumn session of parliament, which begins on Monday.
Three days have been set aside in the third week of the session to debate the issue.