Hi
Basically no.
But if you locked a folder (I assume you mean so that the apps within it cannot be run) then you don't achieve much, because the apps could be accessed from the app drawer, settings, play store or various other ways. You would be better to actually lock all the apps within the folder using an app such as App Lock (Domobile) and then disabling them all at the same time with one click (just one password entry to re-enable them all).
If you mean lock the folder so it cannot be moved or have its contents altered, many launchers have a "lock desktop" feature which is really intended to prevent accidental changes. (But I dont know which phone or launcher you are using)
Roger