Objective To establish a classification in subgroups with symptoms and functionality involving volunteers with nonspecific chronic low back pain for better clarity of functional and therapeutic diagnostic definitions. Methods Observational, quantitative, cross-sectional study with population of 62 university students between 18 and 30 years of age, with a mean age of 21.40 (± 2.40) years, presenting nonspecific lumbar pain for more than three months. Three questionnaires were used for the division into subgroups: STarT Back Screening, the Oswestry Disability Index, and FABQ-Brasil, the VAS evaluation, orthopedic tests: Lasègue’s, Slump test, de Sèze test, Valsalva maneuver, and evaluation of the pain threshold of the right and left iliocostal lumbar muscles. Results All the volunteers included in the study had chronic back pain. Most of them (50%) had normal body mass index, 54.8% were sedentary, and of those who were physically active, 14.5% did body building. The Slump test (35.5%) proved to be more reliable than Lasègue’s test (21%). In the evaluation, the volunteers reported moderate pain intensity (72.6%) and the mean pressure pain threshold was 6.37 kgf and 6.14 kgf for the right and left iliocostal muscles, respectively. In the questionnaires, 85.5% had a low-risk score, that is, a good prognosis for pain treatment, and 91.9% had minimum disability. The largest treatment hypothesis group was stabilization (29.0%). Conclusion The method of treatment subgroup classification is a guide towards better semiological perspectives and the definition of the clinically preferred physiotherapeutic treatment for each case. Level of Evidence III; Diagnostic study.