We propose and demonstrate the Large-Mode-Area-WType Double Clad Fiber (LMA-W-DCF) for high power fiber laser system. The proposed fiber structure is capable of filtering the higher order modes of the system. Using the in-house fabricated fiber, we achieved output power of about 630 W with optical to optical slope efficiency of about 68 % and M-x,y(2) of 1.42 and 1.38 respectively.