Field experiments were conducted at the farmer's field, Madathanoor village, Pochamapalli taluk, Krishnagiri district, from August to January 2023-2024 and at the Experimental Farm, Department of Agronomy, Faculty of Agriculture, Annamalai University, from January to June 2024 to study the yield maximization through agronomic strategies under high-density planting system (HDPS) of cotton. The field experiment was laid out in a factorial randomized block design with three replications. The experiment comprised 12 treatment combinations containing three levels of nutrients and four levels of spacing. The nutrient levels of N1- 80:40:40 nitrogen, phosphorus, potassium (NPK) kg ha-1 , N2 - 100:50:50 NPK kg ha-1 and N3 - 120:60:60 NPK kg ha-1 recommended doses of fertilizers (RDF) were tried with S1 - 60 x 10 cm, S2 - 60 x 15 cm, S3 - 70 x 10 cm and S4 - 100 x 10 cm spacing. The results revealed that the combination of 120:60:60 NPK kg ha-1 + 60 x 10 cm spacing registered higher plant height. Also, the combination of 120:60:60 NPK kg ha-1 + 100 x 10 cm spacing registered higher leaf area index (LAI) and dry matter production (DMP), yield attributing characters (sympodial branches plant-1 , number of squares plant-1 and boll weight) and seed cotton yield. In controversially, the combination of 120:60:60 NPK kg ha-1 + 60 x 10 cm spacing registered higher plant height.