Linkola grew up in Helsinki, spending the summers in the countryside, at the farm of his grandfather Hugo Suolahti. His father Kaarlo Linkola was the Rector of Helsinki University and his grandfather had worked as the Chancellor of that same university. Pentti Linkola chose not to continue his zoological and botanical studies after his first year.

In the essay collection Unelmat paremmasta maailmasta (Dreams about a Better World) (1971) he explained for the first time his ecological attitudes. He has continued to speak against the modern Western way of life and the overconsumption of natural resources. His latest books Johdatus 1990-luvun ajatteluun (Introduction to the Thinking of the 1990s) (1989) and Voisiko elämä voittaa? (Could Life Prevail?) (2004), translated in 2009 into English as Can Life Prevail? are collections of his writings that have been published in various Finnish newspapers and magazines.

As a philosopher Linkola can be described as a biocentric empiricist. His website states that in the West his ideas are considered to be "fascist" and "made taboo". He demands that man return to a smaller ecological niche and abandon modern technology and what he describes as the almost-religious pursuit of economic growth. Linkola considers human population growth the biggest threat to life on Earth.

Linkola's first political publication was the pamphlet Isänmaan ja ihmisen puolesta (For Fatherland and Man) (1960), in which he spoke strongly for pacifism and encouraged conscientious objection. In contrast, in 2004 he derided those he considers to be "sanctimonious in their opposition to violence," when the earth is suffering from severe human overpopulation.

He advocates eugenics, genocide,and abortion as possible means to combat overpopulation. He describes the Stalinist and Nazi massacres, as "massive thinning operations," but which have "not overturned our ethical norms". He has suggested that big cities should be attacked by "some trans-national body like the UN", with nuclear weapons or with "bacteriological and chemical attacks".. Linkola has described humans as a cancer of the earth, and he desires that the human population "be reduced to about ten percent of what it is now."

Linkola often expresses his admiration for forests and nature in general. He is known for his deep love of birds. He considers education to be the "most precious aspect of society," and advocates for universities to be maintained regardless of the cost. In a 2004 interview given at the international bookfairat Turku Linkola describes the origins of his bitterness towards humankind. In his essay, Women as Protectors of Life, he opines that the "soul of a man, beneath its rough surface, is paradoxically more sensitive, fragile and weak than that of a woman."

Ideally, Linkola believes that Finnish society should be ruled by an environmentally-aware elite. He writes that this elite would ban almost all use of motorized vehicles, and transfer populations from bigger cities to the countryside to create an agrarian society. This would eliminate the need for parking lots and construction, and trees would be planted on major roads. Industrialists and technologists would be retrained as agricultural labourers. Procreation would be licensed, with an average of one child born to each woman. Local autarchy would reduce the need for travel, which would be done by foot, paddling, horse or bicycle, instead of by cars, airplanes or motorboats.

• Linkola, Pentti & Olavi Hilden: Suuri Lintukirja. Otava 1955, renewed edition 1962.
• Isänmaan ja ihmisen puolesta: Mutta ei ketään vastaan. Fourth edition. Helsinki: Suomen sadankomitealiitto, 1981 (third edition 1970).
• Linkola, Pentti: Pohjolan linnut värikuvin: Elinympäristö. Levinneisyys. Muutto. Otava 1963–67.
• Linkola, Pentti: Unelmat paremmasta maailmasta. Fourth edition. Porvoo: WSOY, 1990.
• Linkola, Pentti: Toisinajattelijan päiväkirjasta. Porvoo: WSOY, 1979.

*In 1983 Linkola received the Eino Leino Award for the book.

• Linkola, Pentti & Osmo Soininvaara: Kirjeitä Linkolan ohjelmasta. Porvoo: WSOY, 1986.
• Linkola, Pentti: Johdatus 1990-luvun ajatteluun. Porvoo: WSOY, 1989.
• Ekologiseen elämäntapaan: johdantoartikkeli. Yliopistopaino, 1996.
• Linkola, Pentti: Voisiko elämä voittaa. Helsinki: Tammi, 2004.
• Linkola, Pentti: Can Life Prevail?: A Radical Approach to the Environmental Crisis. UK: Integral Tradition Publishing, 2009 (English translation of Voisiko elämä voittaa).

Also:

• Kämäräinen, Kauko: Linkola, oikeinajattelija. Tampere: Määrämitta, 1992.
• Alén, Eero: Linkolan soutajan päiväkirja. Turku: Sammakko, 2006.