With accent marks:
Де́лу вре́мя, поте́хе час.
Time for business, an hour for fun.
This is the expression of the Russian Tsar Alexei Mikhailovich (1629 - 1676) written by him in a book dedicated to falconry.
Meaning: most of the time shoud be dedicated to business (work) and duties, and less time - to entertainment.
It is usually said as a reminder to a person who, having fun, forgets about his duties.
Other Russian proverbs
Do not chop the branch you sit on
If you like sledding, you should like to carry the sled.
There are no friends for taste and color.
Strike the iron while it's hot.
Better late than never.
The further into the forest, the more firewood is there.
Where there is no fish even a crayfish is a fish.
A well-fed man does not understand a starving one.