Kenny MacAskill joined representatives from Police Scotland, Trading Standards and the Home Office for discussions on how to deal with the increasing problems posed by new psychoactive substances (NPS).
The summit addressed issues such as product safety and consumer protection powers, enforcement and prevention, and looked at powers available to local government.
Legal highs were involved in 47 deaths in 2012 and hundreds more people across Scotland have been admitted to hospital after taking them in the past five years.
Substances sold as legal highs are produced to have similar effects to drugs such as Ecstasy, but they fall outside the UK Government's misuse of drugs laws.
Mr MacAskill warned people to avoid them ahead of the summer music festival season.
He said: "Just because they are legal doesn't mean they are safe. Just because they are not illegal doesn't mean they can't cost you your life or cause other serious harm.
"We have to address supply and do that through law enforcement, but we also have to address demand. Young people have been trying this and some have sadly lost their lives at all too young an age."