An investigation on impact of training and demonstration programme on composite fish culture (CFC), for farmers of Papum Pare district Arunachal Pradesh, were undertaken to ascertain technical knowhow on standard package of practices for successful CFC with six parameters viz, 1. Fish species selection, 2. Fish species ratio combination, 3. Fish seed stocking stages (fry and fingerling) 4. Fry/fingerling treatment (NaCl), 5. Fish stocking density, 6. Pre and post-stocking management. Six villages were selected namely: Mani, Midpu, Chiputa, Balapu, Emchi and Upper Jumi.; 30 fish farmers from each village comprising 180 farmers were part of investigation. As per the baseline survey in the beginning on average 80% of farmers had a low level of knowledge about fish species selection followed by 12% medium and 8 % high. 82% had a low level of knowledge about, fish species ratio combination, 10% medium and only 8% had high knowledge on CFC. 81% had a low level of knowledge on fish seed stocking stages (fry and fingerling) followed by 10% and 9% respectively for medium and high. 91% had a low level of knowledge on fry/fingerling treatment (NaCl), followed by 6% medium and 3% high. 78% had low knowledge on fish stocking density followed by 13% and 9% for medium and high. 86% had low knowledge on pre- and post stocking management followed by 8% and 6% for medium and high respectively. After imparting training and Front line demonstration (FLD) programme at farmers door step on successive year, knowledge on fish species selection for low medium and high was 9%, 11% and 80 % respectively. 20%, 41% and 39% for low, medium and high on fish species ratio combination, 9%, 13% and 78% on fish seed stocking stages. 16%, 36% and 48% for low, medium and high knowledge on fry/fingerling treatment (NaCl), 11%, 19% and 70 % for low, medium and high knowledge on fish stocking density and 15%, 21% and 64% for low, medium and high knowledge on Pre and post-stocking management. Average fish production increase from 0.78 tone/ha/yr to 1.54 tone/ha/yr (97.4% increase) after imparting training and demonstration, which implies training and demonstration on CFC has significant impact on increase fish production per hectare of pond, through the power of knowledge gained by farmers on technical knowhow on CFC.