Objectives: The purpose of the study was to compare low-level laser therapy (LLLT) and local corticosteroid injection in the treatment of plantar fasciitis. Patients and methods: This retrospective study was performed with 56 patients (6 males, 50 females; mean age: 44.7±10.1 years; range, 18 to 65 years) between January 2015 and March 2016. The patients were equally divided into two groups: Group 1, comprising patients who underwent a one-time local corticosteroid injection into the heel by the same physician, and Group 2, including patients who had gallium arsenide laser therapy at a wavelength of 904 nm lasting 10 sessions. Evaluations were done at pre-treatment, post-treatment, and two weeks, one month, and three months after the post-treatment evaluation. The post-treatment evaluation was accepted as the 10th day after the injection in Group 1 and as the time after the last session of the laser treatment in Group 2. Each visit was compared with the previous visit for within-group analysis. The Visual Analog Scale (VAS), Heel Tenderness Index (HTI), and Foot Function Index (FFI) were assessed. Results: Pain scores in Group 1 and Group 2 were not associated with statistically significant differences (p>0.05). Within-groups analysis demonstrated statistically significant differences concerning VAS subgroups (p<0.05), except for Group 2’s resting VAS values (p=0.159). No statistically significant differences were found between groups in the means of FFI scores (p>0.05). Statistically significant differences were observed regarding within-group analyses for all subscores (p<0.001). No statistically significant differences were observed between the two groups for all visits regarding HTI scores (p>0.05). Statistically significant differences were found between baseline and the first after-treatment visit in all groups (p<0.05). Statistically significant differences were found in the first (p=0.020) and third (p=0.010) months compared to the one-week follow-up in Group 2 regarding HTI scores. Conclusion: Both LLLT and local corticosteroid injection for plantar fasciitis have positive effects for three months after treatment. However, LLLT is more effective than local corticosteroid injection at the end of the third month in local tenderness.