An Investigation of estimated Mechanical Properties of AL-Alloys 6061-T6, which is one of the most commonly used in industrial applications, has been established experimentally. A new novel Plasma Peening techniques had been applied to the whole surfaces of the material by CNC-Plasma machine for 48 specimens, and then a new investigation were takeover to figure the amount of change in mechanical properties and estimated fatigue life. It was found that the improvement was showing a nonlinear behavior, according to peening duration time, speed, peening distance, peening number, and amount of effected power on the depth of the material thickness. The major improvement was at medium speed long duration time normal peening distance. Which shows up to 4 times improvements than the other cases. It was found that reducing in elongation of about 25% from references for 1x plasma peening for the most techniques used while a reduction in elongation of 31% for the two time plasma peening, on the other hand increment of 10% in elongation for 2x plasma peening and 5% of the increment for peening with 5kW of plasma power. These results illustrated in both tables and figures. Further study may established for other AL-Alloys to study the effects of plasma peening on it and to find the most effected one of them for the completely nine AL family.