League spokesman Juan Carlos Santamaria has confirmed that they are examining Depor's 4-0 win at the Estadi Ciutat de Valencia on 13 April.
Levante have issued a statement on their website saying they will "help and collaborate with any investigation."
Deportivo, who are currently in administration and one point outside the relegation zone, scored three times during the first half.
At the interval, Levante midfielder Javier Barkero reportedly accused his team-mates of not trying, which sparked a dressing room confrontation.
"I have asked for forgiveness from everyone and especially my four colleagues whom I have wrongly accused," Barkero said on Wednesday.
"I was wrong. I accused them of something that hadn't happened and I want to make that point."
Match-fixing is a crime in Spain and can lead to prison time for individuals or expulsion of a club from official competition.