it depends on where you are MWB
Here is a piece of an article I found,
Hope it helps.
Drivers should be aware that in most regions, it is illegal to drive at night with just parking lights on, although leaving running lights on during the day is perfectly legal, and in fact, encouraged. In most US states, however, it is illegal to drive with just your parking lights on whether in the day or night. You should consult the the appropriate regulatory body to be sure of the rules that affect you.
Pete.