Roger Bruce Chaffee was born on February 15, 1935, in
Grand Rapids, Michigan,
 the second child of Donald Lynn Chaffee (an American citizen of Lebanese descent) and Blanche May (Mike) Chaffee
:136 He had an older sister, Donna, born two years earlier.
:17 In January 1935, in their hometown of
Greenville, Michigan, his father was diagnosed with
scarlet fever, and Mike moved in with her parents in Grand Rapids, where Roger was born. The family spent the next seven years in Greenville before moving to Grand Rapids, where his father took a job as the chief Army Ordnance inspector at the Doehler-Jarvis plant.
Chaffee excelled as a
Boy Scout, earning his first
merit badge at the age of thirteen. He earned ten more badges that year. Many of these awards were typically won by the older scouts.
:32–33 He continued his success by obtaining four additional badges at the age of fourteen.
:33 He won four badges for each of the next two years, and had earned almost all the badges available at the time. After becoming an
Eagle Scout, he managed to earn another ten merit badges, for which he was awarded the bronze and gold palms.
Chaffee attended the Dickinson School in Grand Rapids.
:136 He graduated in the top fifth of his class from
Central High School in 1953.
:43 Turning down a possible appointment to the
United States Naval Academy at
Annapolis, Maryland, he accepted a
Naval Reserve Officers Training Corps (NROTC) scholarship, and in September 1953 enrolled at the
Illinois Institute of Technology. He performed well, making the
Dean's list and finishing with a B+ average. While enrolled, he joined
Phi Kappa Sigma.
Chaffee was passionate about flying, and had a strong aptitude for science and engineering. To apply those talents, he transferred to
Purdue University in the autumn of 1954 to attend the school's well-known
aeronautical engineering program.
 Prior to his arrival in
West Lafayette, he reported for an 8-week tour on
USS Wisconsin as a part of the NROTC program. To qualify, he had to finish training and pass additional tests. He initially failed the eye exam, but the physician allowed him to retake the test the next morning, and he passed. He was then allowed to tour on Wisconsin to England, Scotland, France, and Cuba. Upon his return to American soil, he worked as a gear cutter.
Upon starting classes at Purdue, Chaffee sought out a job to complement his coursework and involvement in the Phi Kappa Sigma social fraternity. His first job during his sophomore year was working as a server at one of the women's residences, but he disliked the job and sought new employment. He was hired as a
draftsman at a local small business near Purdue. As a
junior, he was hired as a teaching assistant in the Mathematics Department to teach classes to
 He also joined the
Tau Beta Pi and
Sigma Gamma Tau engineering honor societies.
While at Purdue, Chaffee took flight training as part of the NROTC program to prepare himself for a career as a
naval aviator, soloing on March 29, 1957, and obtaining his
private pilot's license on May 24, 1957.
 He earned a
Bachelor of Science degree in Aeronautical Engineering at Purdue in 1957.
Chaffee married Martha Louise Horn in
Oklahoma City on August 24, 1957; they had met on a blind date in September 1955.
 Martha was a homemaker.
:67 The couple had two children, Sheryl Lyn (born in 1958) and Stephen (born in 1961).