Without knowing the context the sentence alone may mean that something was caused by bad luck. It is not indispensable to use the verb "dar" in this case.
If the verb "dar" is not used an equivalent sentence may be "Le parece que esto fue mala suerte" or "Le parece que esto es mala suerte". The sentence is not saying that something gave bad luck to someone, just that something was bad luck, that there was or there is bad luck involved.
The situation caused by bad luck could be affecting several people, not a specific person: "Hay una tormenta y se suspendió el vuelo. Esto le parece mala suerte."
If the intention is to say that something causes bad luck then the preposition "de" should be used (not "da"): "Esto le parece de mala suerte".
If the word "da" (from the verb "dar") is to be used then the sentence should be: "Le parece que esto da mala suerte". The sentence "Esto le parece da mala suerte" is unnatural for a native speaker.
It may be necessary to know the context to give a precise answer and to know if the sentence is correct or not in that context.