Michael Matheson spoke out as an expert group set up to try to reduce that gap met for the first time.
The Ministerial Taskforce on Health Inequalities was established to suggest ways to tackle the problem. It comes after a report published last year showed life expectancy was higher where deprivation is lower.
It found men in the wealthiest areas could expect to live for 81.4 years, 13.2 years longer than males in the most deprived areas.
For women, those living in the most affluent areas of the country can expect to live to 84.6, nearly nine years longer than those in the poorest communities.
Mr Matheson said: "While health in Scotland continues to improve and people live longer, health inequalities are still worse than in the rest of western Europe.
"Of all the challenges facing Scotland, the health gap between rich and poor is among the greatest."
He argued that reducing these inequalities would "improve Scotland's wellbeing and ease pressure on public finances".
Mr Matheson said: "The challenge for the taskforce is to review the effectiveness of current policy and to hear community views on the best way ahead."