JOHN CHEEVER: A BIOGRAPHY; By Scott Donaldson; Random House; $22.50, 416 pagesBeneath John Cheever's winsome facade - the face of an elf, the buttoned-down attire of a preppie, the conversational style of a wag, the drinking habits of a rogue, the stories and novels that some observers mistook for comfortable celebration of America's upper-middle class - lay a lifetime of pain.

The Pulitzer Prize, the National Book Award, the National Medal of Literature, the fame and fortune of best-sellerdom came late in life. To get there, according to biographer Scott Donaldson, Cheever had to overcome the lingering effects of inattentive parents who hadn't wanted a second child. Ever after, he had to fight off the feeling of being unloved.

Ultimately, Cheever triumphed over alcoholism and depression. But his sexuality remained permanently confused. While married and involved with other women, he also practiced a furtive homosexuality he never could fathom.

Some of this story we've heard before, thanks to his daughter Susan's revealing and loving memoir, "Home Before Dark." But "John Cheever: A Biography" is clearly an indispensable book. This first full biography - based on Cheever's letters and journals and numerous interviews with family members and friends - greatly extends our knowledge of one of 20th-Century America's premier writers.

Cheever was a master storyteller, and not only in his fiction. Donaldson sorts through the tall tales the writer liked to tell about his background. Cheever's father, Frederick Lincoln Cheever, for instance, was not the owner of a shoe factory in Cheever's hometown of Quincy, Mass., but a traveling salesman who sold shoes. When Frederick lost his job in the 1920s and became an alcoholic, his wife, Mary Devereaux Liley, once prominent in Quincy community affairs, was forced to open a gift shop to support the family. All this was further humiliation for young John, previously informed that his older brother Fred was all the progeny his parents ever wanted.

Out of his departure from Thayer Academy (whose cause is still unclear, though certainly not the smoking Cheever has cited), he crafted at 18 his first published story, "Expelled." It appeared in The New Republic, whose literary editor, Malcolm Cowley, eventually became a mentor and father figure. Aside from his brother Fred, whom he both loved and unaccountably hated, the young Cheever was also encouraged by novelist Josephine Herbst and Elizabeth Ames, administrator of Yaddo, the writer's colony. They became his surrogate family, his only college.

The Cheever marriage, according to both partners, was a constant struggle. Strong-willed and tart-tongued, they fought, ignored each other, took separate vacations, yet never divorced. In his journal, he complained, "I am not allowed a kiss; I am barely granted a good morning." No wonder. He ridiculed Mary's teaching at Briarcliff College and openly carried on numerous affairs, including a long relationship with actress Hope Lange. As he got older, he turned more often to men.

By the mid-'70s, the writer descended into a nightmare of alcohol. The Cheever bonhomie could no longer disguise his wretchedness. At the Iowa Writers' Workshop, he and Raymond Carver stood in the morning light waiting for the liquor stores to open. His journal read: "Scotch for breakfast and I do not like these mornings." He stumbled from drunkenness to remorse and back again.

Before cancer finally killed him in 1982, Cheever made the triumphant journey from dark to light. He quit the booze, wrote the acclaimed "Falconer," his "Stories of John Cheever" won the Pulitzer and he achieved a serenity and "generosity of spirit" he'd never before experienced.

It's a gut-wrenching story. Donaldson tells it straight, without embellishment, and our attention never strays.