George Lyon told the Scottish party's conference in Aberdeen the positive attitude of the LibDems to the community was in contrast with those of their rivals.
Mr Lyon appeared to echo Deputy Prime Minister Nick Clegg, who drew a partial comparison between Alex Salmond and Nigel Farage in his speech on Friday.
Rounding off the conference yesterday, Mr Lyon told delegates: "We achieve so much more when we work with those around us. Ukip and the SNP of course disagree with that point of view.
"They say that Britain and the EU are holding Scotland back. We say they are helping us to achieve more.
"Together in the UK we created the NHS, the state pension, the minimum wage and a proper safety net for those who are unable to work. As part of the European Union, the UK family helped create the biggest single economy in the world and in doing so we have bound together countries that had previously been riven with conflict and war."
He said being part of something bigger, such as Europe, gave the party the best chance of fulfilling its potential.
He claimed Mr Clegg, the LibDem leader, had made Ukip leader Nigel Farage "a little sweaty and uncomfortable last week" as he laid bare Ukip's bluff and bluster in a TV debate.
He cited: "Their claims on immigration, their claims on the cost of the EU, their claims on who really makes our laws, exposed as fantasy, not facts. As Nick said in the debate, being in is about jobs in Scotland and across the UK. Three million British jobs are linked to our being in the EU market, the biggest economy in the world.
"Putting even one of these jobs at risk by pulling up the drawbridge is one job too many."
Denying the SNP's claim EU entry could be negotiated by Scotland and achieved in 18 months, he said: "I am not sure what the French or Spanish is for 'Aye right'.
"But let me tell you, the shortest time it has taken any new member to join the EU since 1995 has been eight years and the Commission tell us that new member states would have to sign up to their rules on currency and borders to secure their entry to the EU club."
The SNP said legal opinion was on their side as Scotland would be the first country to negotiate entry from within.
They said: "The irony is that the Liberal Democrats are standing shoulder to shoulder with the Europhobic Ukip in both seeking a No vote in Scotland's referendum."