A field experiment was conducted in clay loam soil (Typic Chromustert ) to study the effect of soil application of lignite humic acid(HA) on the growth and yield of rice fallow cotton. The soil analysed the pH 7.6, EC 0.34dSm-1, organic carbon-4.5g kg-1, available N (KMnO4 oxidisable N) 207.9 kg ha-1, available P (Olsen P) 16 kg ha-1 and available K(NH4 O Ac – extractable K) 349.1 kg ha-1. The treatments consisted of three levels of NPK (soil test based recommendation). F0 –Control, F1 -75 % NPK and F2 -100 % NPK and four levels of humic acid (0, 25, 50 and 75 kg ha-1). Cotton var- MCU-12 was grown as a test crop. The experiment was carried out in Factorial randomized block design(FRBD) with three replications. Calculated quantity of N, P2 O5, K2O were supplied through urea, DAP and muriate of potash to the plots as per the treatments. Humic acid extracted from lignite was applied to the required plots as per the treatments as K- Humate. Yield characters like number of bolls per plant and boll weight and seed cotton yield were recorded in each harvest in all the treatments. The plant sample collected in each experimental plot were analysed for its NPK content The results revealed that increasing levels of HA increased the growth and yield of cotton. Addition of NPK had a significant increase in the yield parameters of cotton. Combined application of HA @50kg ha-1 along with 100%NPK recorded the highest NPK uptake as well as the seed cotton yield of 2881 kg ha-1. This was followed by the treatment which received 100%NPK along with HA@25 kg ha-1. The yield characters like numbers of bolls per plant-1 and boll weight are also significantly improved by both HA and NPK application. The uptake of NPK by cotton was increased with increasing level of HA as well as NPK. Combined application of HA@50 kg ha-1 and 100% NPK recorded the highest NPK uptake of 169.91, 20.1, 176.69 kg ha-1