Here, 1,100 plant species and subspecies can be found, 92 of which are Greek endemics. Parnitha has 3 vegetation zones dictated by the mountain's altitude. The first zone extends from 300-800m and is dominated by pine forests and phrygana. The second zone extends from 900-1,400m and is dominated by fir forest, brushwood, and grassland. Lastly, the third zone is observed on the highest mountain summits and consists of spiny bushes.

In the past, most of the country's large mammals were present on the mountain. Today, Parnitha's fauna remains among the richest in Attica and sustains a significant number of red deer, 23 bird species, 12 mammal species, and 12 amphibian/reptile species. The wildlife of the mountain includes 11 endangered and 8 vulnerable species. The morphology of the area - mainly limestone and schist - resulted in the creation of 46 springs and streams that continuously flow and form several small ponds.

Parnitha is a popular destination, which supports many leisure and sporting activities such as hiking, rock climbing, mountain biking, trekking, and more. There are 2 cozy and very welcoming, ridge shelters for resting or sleeping. One is at Mpafi, owned by the Hellenic Alpine Club of Athens, and the other is at Flampouri, belonging to the Hellenic Alpine Club of Acharnes.

Outside of the heart of the park lies the Regency Casino Mon Parnes, a luxurious resort for gambling with accommodation services and a gourmet restaurant. Visitors can reach the casino on Mount Parnitha easily by cable car. The view on the way up is breathtaking.