Background: DH is an extreme reaction to sensory stimuli that, in most cases, wouldn't cause any problems for a tooth that is healthy and normal. The present study was conducted to assess effect of diode laser treatment and casein phosphopeptide-amorphous calcium phosphate paste on eroded root dentin. Materials & Methods: 45 bovine root dentin specimens which were divided into 5 groups. Group I was control group without erosion-sound dentin, group II was control group eroded: specimens were eroded and did not receive any pretreatment, group III was casein phosphopeptide-amorphous calcium phosphate fluoride (CPP-ACP): specimens were pretreated with CPP-ACP, group IV was diode laser: specimens were irradiated with a wavelength of 970 nm, and in group V CPP-ACP + diode laser: specimens were pretreated with CPP-ACP for 5 min and simultaneously irradiated with laser on contact mode. The quantitative bond strength, prevalent fracture mode and the morphology of the dentin surfaces after treatment was recorded. Results: The mean shear bond strength in group I was 19.7 MPa, in group II was 14.3 MPa, in group III was 25.9 MPa, group IV was 16.2 MPa, and in group V was 20.7 MPa. The difference was significant (P< 0.05). Fracture type was adhesive at the interface, mixed, cohesive composite resin failure, and cohesive dentin failure in group I seen in 85%, 5%, 4% and 6% respectively. In group II was 82%, 4%, 7% and 7% respectively. In group III was 80%, 7%, 8% and 5%. In group IV was seen in 81%, 10%, 7% and in 2% respectively. The difference was significant (P< 0.05). Conclusion: The use of CPP-ACP-containing desensitizers, whether or not they were coupled with a diode laser, strengthened the binding between the eroded root dentin and the etch-and-rinse adhesive system.