Purpose: This study aimed to investigate in-depth causes of slump, symptoms and factors leading professional golfer's bounce-back and present phenomena and psychology in the course of time, provided that it accords to the phenomenon that professional golfers’skill sets are improved after a period of slump is defined as “slump bounce back.” Methods: Subjects of study were 4 male golfers and 5 female golfers. Results were extracted from in-depth interviews. Results: In causes of professional golfer’s slump were from faulty swing, inefficient practice, lack of practice, plateau condition, injury, problems of physical strength, health issues, boredom, criticism from surrounding people, stress from comparing with fellow golfers, pride, uncertain goals, etc., and environmental causes were from financial problem, personal relations, conflict with instructors, change of environment, etc. In symptoms included continuously worsening skills; physical symptoms included insomnia, worsening health, physical exhaustion, hair loss, subjects experiencing negative emotions, psychological isolation, a drop in psychological functions, financial problem, relationship with parents, attitude from surrounding people, etc. As for the factors for depressed golfers to bounce back, it was due to continuous practice, change of methods, improved scores and techniques, physical maintenance, positive change in emotions, training in psychological techniques, financial comfort, parental support and instructor’s help, fellow golfer’s roles, special opportunities, etc.