Abstract: Background: Periodontal diseases a group of microbial infections that’s found in gingiva and supporting tissues of the teeth. The effect of microorganisms in the periodontitis could be confirmed. Purpose: The current study was conducted to evaluate the effects of Diode laser versus PDT in periodontitis treatment as non-surgical method of treatment. Materials and methods: Thirty patients’ males and females suffering from gingival pockets with age range from 20 to 65 years old from faculty of oral and dental medicine out clinics and selected randomly and divided in 2 groups each group contains fifteen patients. Group A received scaling and root planning in addition to 980 nm diode laser while Group B group received scaling and root planning in addition to PDT. Results: showed statistically significance improvement in group A (F=114.697, P=0.000) and in group B (F=126.308, P=0.000). Also, there was statistically significant difference between the two groups (F=5.904, P=0.000) with most difference in Pocket depth only (F=21.122, P=0.000) with statistically significant differences in post treatment value (F= 2.333, P=0.000) and follow up at one (F=0.700, P=0.019) and six months (F=1.100, P=0.000). Conclusion: Both PDT and Diode therapy have significant effect in pocket depth, bacterial count and bleeding examination in periodontitis treatment, but PDT have Superior effect when pocket depth is the target.