VisitScotland said the top five words used by tourists to describe Scots they met were "friendly", "helpful", "welcoming", "nice" and "warm".
And 82% of visitors agreed local people added to their holiday experience.
The survey of nearly 6,000 tourists last summer is the biggest of its kind VisitScotland has produced.
While landscape and scenery remained the number one reason why people visited Scotland (49%), the nation's reputation for friendly people was cited by 15% as a major draw.
Visitors also said the people of Scotland were an important source of information for things to see and do during their stay, with about half (49%) talking to local people for advice.
Perhaps surprisingly, climate also featured in the list of top reasons why tourists chose to visit Scotland, with 5% travelling to enjoy the weather.
Nine out of ten visitors said they would recommend Scotland as a holiday destination, while six out of ten felt Scotland was a country worth visiting more than once.
Top ten words visitors used to describe people they met in Scotland:
• Friendly - 50%
• Helpful - 25%
• Welcoming - 12%
• Nice - 6%
• Warm - 5%
• Interested - 3%
• Kind - 3%
• Open - 3%
• Happy - 2%
• Fun - 2%
Tourism Minister Fergus Ewing said: "Scotland's people are its greatest asset, especially in an industry like tourism where - as this survey shows - our warm welcome, and friendly approach, have helped to define and enrich the experiences of thousands of visitors across the length and breadth of the country.
"The latest survey highlights the huge draw of Scotland's jaw-dropping scenery, our vibrant culture and rich history, while also confirming the important role that everybody, from those in the industry to passers-by in the street, plays in ensuring all our visitors leave with fond memories, having enjoyed their stay to the utmost."
Last month VisitScotland launched a new £4.25m tourism campaign aimed at promoting the "spirit of Scotland".
The organisation came up with seven traits it believed could be found within the characters of the people and landscapes of the country - warmth, humour, guts, spark, soul, determination and fun.
Using the hashtag #ScotSpirit the organisation hopes to encourage people across the world to share what Scotland means to them.
Scotland's reputation as a nation of friendly people has been highlighted in a major survey of visitors by the country's national tourism body.