A new survey of almost 15,000 wildlife enthusiasts by RSPB Scotland showed the prickly creatures were seen in 57% of gardens and outdoor spaces.
In the 1950s it was estimated there were more than 30 million hedgehogs in the UK.
But recent figures suggest there are now less than one million left.
The study also found participants from just 2% of gardens managed to catch a glimpse of the elusive great crested newt, an amphibian found in only a few areas of Scotland.
Moles also remained elusive to the majority of the 9,700 gardens that recorded wildlife, with the creatures or one of their molehills going unseen in more than half of outdoor spaces.
The rarity of these animals was at odds with foxes, who were the most common garden visitor with 64% spotting at least one throughout the year.
James Silvey, all nature species and habitat officer at RSPB Scotland, said: "Unfortunately, such garden wildlife and the sounds and sights it creates are becoming less and less familiar for many people.
"With the wildlife on people's doorsteps becoming increasingly mysterious to them, RSPB Scotland is calling on families to spend more time outside this summer and reconnect with the nature that surrounds them by taking on the Wild Challenge.
"By completing fun and engaging activities ranging from mini-beast safaris and rock pooling to creating a hedgehog cafe and planting for wildlife, families can take their first steps on their own wild adventure."
Hedgehogs were spotted in more than half of Scottish gardens in a study last year despite years of concern about their plummeting population.