Abstract: Basic physiology, hematology and serum chemistry of indigenous chicken, reared in eco-friendly environment of backyard of small farmers in temperate regions of J and K State (altitude range 1500-2000 m amsl, average temperature 13°C), was studied in adult chicken from different pockets of Kashmir. The average values for haemoglobin (Hb), Packed Cell Volume (PCV), Total Leukocyte Count (TLC), Total Erythrocyte Count (TEC), Mean Corpuscular Volume (MCV), Mean Corpuscular Haemoglobin (MCH), Mean Corpuscular Haemoglobin Concentration (MCHC) were 13.21±0.39g%, 40.70±0.51%, 16.80±0.47×103/cumm, 3.20±0.07×106/cumm, 127.18±2.68fl, 41.28±0.56pg, 32.45±0.57g% and 11.32±0.19g%, 35.21±0.61%, 22.29±0.37×103/cumm, 2.98±0.08×106/cumm, 118.15±1.76 fl, 37.98±0.56pg, 32.14±0.39g% in cock and hen respectively. Percentage presence of different leukocytes in blood was 32.55±0.61, 48.87±0.81, 10.90±0.35, 5.67±0.24, 2.05±0.18 and 26.32±0.46, 49.98±0.72, 10.85±0.36, 8.69±0.26, 3.19±0.23 for heterophils, lymphocytes, monocytes, eosinophils, basophils respectively in cock and hen. The cytometry of erythrocytes revealed 13.86±0.11 micrometre and 12.78±0.09 micrometre length, 8.37±0.09 micrometre and 7.86±0.07 micrometre breadth in cock and hen respectively. The values for Hb, PCV, TLC, TEC and RBC size differed significantly (p<0.01) among the cocks and hens. Serum was analysed for glucose, cholesterol, total protein, albumin, globulin, uric acid, creatinine, calcium, phosphorus and alkaline phosphatase, the average values recorded were 227.83±6.07 mg dL-1, 116.33±4.90 mg dL-1, 3.99±0.18 g dL-1, 1.78±0.06 g dL-1, 2.15±0.17 g dL-1, 6.31±0.33 mg dL-1, 1.54±0.17 mg dL-1, 10.79±0.50 mg dL-1, 4.19±0.20 mg dL-1, 9.84±0.67 K.A.U and 227.43±4.93 mg dL-1, 141.02±5.36 mg dL-1, 4.97±0.16 g dL-1, 2.20±0.07 g dL-1, 2.79±0.14 g dL-1, 6.21±0.40 mg dL-1, 1.62±0.08 mg dL-1, 12.01±0.47 mg dL-1, 4.74±0.30 mg dL-1, 11.11±0.84 K.A.U in cock and hen respectively. The values for cholesterol, total protein and albumin differed significantly (p<0.01) among the sexes where as no significant difference for glucose, uric acid, creatinine, calcium, phosphorus or alkaline phosphatase was observed. Besides haematology and serum chemistry, heart rate, respiration rate and rectal temperature were recorded and the values were 285.80±6.78 beats/min and 359.92±8.48 beats/min, 27.29±0.49/min and 31.10±0.32/min, 105.59±0.14oF and 106.31±0.09oF in cock and hen respectively that differed significantly (p<0.01) among sexes. Mean electrical axis of QRS was -81.4±1.97o and -78.38±1.76o in cock and hen respectively. The time intervals of different phases of cardiac cycle in cock and hen were 205 ms and 169 ms, 59.16 ms and 49.44 ms, 102.5 ms and 87.77 ms and 23.75 ms and 12.5 ms for R-R, P-R, R-T and T-P intervals respectively. The study revealed significant effect of sex on various physiological parameters in native chicken of Kashmir.