The poll asked 1,000 Finns if they would support a military union where the armed forces of either country could be called upon for support in a crisis situation, reported Finnish public broadcaster YLE.
Fifty-four percent of respondents said they were in favour of a union, while 36 percent were opposed to it. The remaining ten percent said they were unsure.
Those over the age of 50 and those under 25 were the most positive to the suggestion.
The survey caught the attention of Finland's Defence Minister Carl Haglund, who said that military alliances "should not be ruled out".
"It creates the conditions, if we know each other better," he told YLE. "If one day we decide to start deeper, political co-operation, then the conditions are a lot better."
Finland, like Sweden, is not a member of Nato and the matter has been a subject of growing debate in both countries following the Russian annexation of Crimea.
According to a report in the Defense News journal both Finland and Sweden are warming to the idea of a "collective defence solution", an idea long favoured by Nordic neighbours Denmark and Norway who are both full members of Nato.
Even prior to the Russian incursion into Ukraine, Sweden's Armed Forces (Försvarsmakten) had been the subject of increased scrutiny ever since Supreme Commander Sverker Göransson said in January 2013 that Sweden could only defend itself for one week.
A poll later in the year showed that public opinion supported Göransson's stance, with only six percent of Swedes believing that the the country's military could defend Sweden against an attack, while 83 percent doubted Sweden could defend itself.