Horses diagnosed with chronic lower back pain were randomized into 2 treatment groups: high intensity laser stimulation of acupuncture points (HILSA) or therapeutic ultrasound (TU) applied to the lower back (T-18 to sacroiliac joint). The horses received a total of 8 treatments administered every other day during the study period (16 days). The reduction of pain between baseline (Day 0) and after treatment (Day 16) was evaluated both by TCVM acupoint sensitivity scan and pressure algometer. The acupoint sensitivity scan demonstrated statistically significant improvement for both treatment modalities. The HILSA Group change (8.13 ± 8.476) was very significant (p=0.0028) with a 66% change from baseline while the TU Group change (3.77 ± 4.38) was also significant (p=0.0223) with a 34% change from baseline. Comparison of the magnitude of improvement between groups was not statistically significant (p=0.0659). Algometer measurements experienced some limitations with inconsistent results. It can be concluded from study findings that both treatment modalities are associated with a statistically significant reduction of lower back pain in sport horses and selection of treatment can be based on the advantages and disadvantages of each modality dependent on the patient and situation.