http://ijeab.com/ Open Access international Journal to publish research paper en-us August A field experiment entitled was conducted during the Kharif season of 2025 at Agronomy Instructional Farm, Rajasthan College of Agriculture, Udaipur. The experiment was laid out in Factorial Randomized Block Design (FRBD) with twelve treatment combinations comprising four potassium levels viz., K0 (Control), K1 (75% RDK), K2 (100% RDK) andK3 (125% RDK) and three organic sources viz., O0 (Control), O1 (FYM @ 10 t ha⁻¹)and O₂ (Vermicompost @ 5 t ha⁻¹), replicated four times. The initial soil was slightly alkaline (pH 8.11), non-saline (EC 0.59 dS m⁻¹), with medium organic carbon (0.60%) and available nitrogen, phosphorus and potassium content of 230.00, 19.10and 402.00 kg ha⁻¹, respectively. After harvest, soil pH and EC remained unaffected by both potassium levels and organic sources. Potassium application significantly increased residual available potassium, with the highest value recorded under 125% RDK (K3), which remained at par with 100% RDK (K2). Organic sources significantly improved soil organic carbon and available nitrogen, phosphorus and potassium status. Vermicompost @ 5 t ha⁻¹ (O2) recorded the highest values of organic carbon (0.676%), available nitrogen (267.08 kg ha⁻¹), available phosphorus (22.61 kg ha⁻¹) and available potassium (455.35 kg ha⁻¹).The study concluded that organic nutrient sources, particularly vermicompost, were more effective in improving post-harvest soil fertility compared to potassium levels alone. The combined application of vermicompost @ 5 t ha⁻¹ with 125% RDK (K3O2) proved beneficial for maintaining soil nutrient status and improving soil health under maize cultivation. http://ijeab.com/detail/comparative-assessment-of-initial-and-post-harvest-soil-chemical-properties-under-different-organic-sources-and-graded-levels-of-potassium-in-maize-zea-mays-l/ Varsha Menaria, K. K. Yadav, D. P. Singh, Brijesh Yadav, H. L. Bairwa http://ijeab.com/upload_document/issue_files/6IJEAB-107202618-Comparative.pdf