Twenty female farmers in each of 20 different villages of district charsadda, NWFP were selected at random to investigate prevalence and economic ramification of Newcastle disease in Backyard chicken. Overall Morbidity and mortality was 31.0±1.84 and 26.98±1.14%, respectively causing 86.95±0.79% mortality among the sick birds. Morbidity (56.93±7.61) and mortality (98.66±7.03%) among the sick birds was higher (p<0.05) in White Leghorn (WLH) than in Fayumi (17.94±2.22 and 74.28±1.91), Rhode Island Red (RIR; 27.79±3.73 and 90.67±3.71) and Local chicken (20.82±1.34 and 84.24±0.89%, respectively). Overall mortality was also higher in WLH (49.23±6.92%) than in Fayumi (14.36±1.89%), RIR (24.10±3.36%) and Local (20.18±1.18%) morbidity (49.19±1.56%), mortality among the sick birds (99.89±0.93%) and overall mortality (44.88±1.45%) was higher (p<0.05) in those flock which were not vaccinated flocks than in flocks regularly vaccinated (12.84±1.01, 65.96±2.02% and 8.92±0.84%, respectively). Morbidity (46.82±2.35%) and mortality among the sick birds (98.58±0.27%) was higher (p<0.05) in chicks than in adult birds (17.63±1.23 and 76.06±1.80%) and pullets (28.92±2.49 and 85.79±0.87%, respectively). Overall mortality was also higher in chicks (40.71±1.52) than in adult birds (15.76±0.91%) and Pullets (24.39±1.07%). Higher morbidity and mortality (among the sick birds) was observed in winter season (72.08±0.84 and 98.82±0.82) than in Summer (29.45±0.78 and 90.93±0.89), Fall (14.63±0.68 and 82.78±1.03) and Spring season (8.28±0.72% and 74.08±1.2%, respectively). Overall mortality was also high in winter (68.7±0.79%) than in Summer (22.34±0.7%), Fall (11.26±0.8%) and Spring (5.65±0.93%). Although, not significant, morbidity and mortality (among the sick birds) was numerically high (32.16±2.01 and 96.43±2.68%) in chicken having no shelter facility than in those which had a night shelter facilities (30.03±1.95 and 77.51±1.79%, respectively). Per cent morbidity had a non-significant association (b=-0.6341±0.085) with per cent reduction in egg production. Per cent morbidity was found significantly (p<0.05) and negatively associated with per cent reduction in eggs of RIR (b=-0.2254±0.572) and local chicken (b=-0.14862±0.047). Per household annual reduction in eggs and economic ramification due to reduced egg production, and mortality were 401.06±1.14 eggs and Rs. 902.45±0.56, and Rs. 1343.84±2.8, respectively. Total per household per year economic ramification due to reduction in eggs and mortality resulting from Newcastle disease was Rs. 2246.29±1.19. Per household per cent reduction in egg production and economic ramification due to reduced egg production of Newcastle affected chicken was higher (p<0.05) in WLH (154.41±1.14 number and Rs. 347.42±5.34) than in RIR (114.89 number and Rs. 258.5±2.15), local (76.04±1.14 and Rs. 171.09±2.26) and Fayumi (55.75±0.45 and Rs. 125.44±3.88, respectively). Economic ramification as a result of mortality was also higher (p<0.05) in WLH (Rs. 457.32±5.91) than in RIR (Rs. 378.39±2.89), local (Rs. 311.6...