This work aims to investigate the effect of two fish farms irrigation sources; Al-Batts Drain, (A) and El-Wadi Drain (B), Fayoum] on quality criteria of fresh Nile tilapia fillets and changes occurring in its proximate composition during frozen storage at -18˚C for 180 days.  Quality indices (pH, TVB-N, TMA-N, TBA and Biogenic amines) and microbiological aspects (total bacterial count (TBC), total coliform count (TCBC) and yeasts and molds ( Y&M) count) of fresh Tilapia fish fillets were determined. , The results showed that the values of pH were 6.18 and 5.95, TVB 15.4 and 12.72 mg/100g, TMA-N  0.78 and 0.60 mg/100gm, TBA  0.77 and 0.51 mg/kg while total Biogenic amines values were 38.01 and 24.71 mg-kg for samples obtained from Farm A and Farm B fresh samples, respectively.. The low counts of TB, TCB and Y&M indicated that to the safety of these samples. The content of moisture, protein, and lipid decreased during frozen storage periods while ash increased in frozen samples to record 5.52 and 5.43 % for samples A and B, respectively.