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Consumers' need for quick-cooking and nutritious rice has increased production of parboiled instant rice. The parboiling process has proven to enhance the nutrition and milling yield of rice. Hot-air oven drying is considered as one of the efficient drying methods; however, the impacts of the rice's initial moisture content (MC) and that of the drying process post-cooking on the quality of parboiled instant rice are not well understood. Therefore, the objective of this study was to assess the impact of initial MC of rough rice and hot-air stepwise oven drying on the quality of parboiled instant rice. Medium-grain cultivar Titan (22.5% MC wet basis) and long-grain cultivar RT 7521 FP (19.8% MC wet basis) were used after being conditioned to 16% MC and 12.5% MC. After parboiling, the samples were dried using natural air (77 °F air temperature and 56% air relative humidity) to 12.5% MC to produce white rice (milled to SLC of 0.4%) and brown rice. Rice was then cooked in excess water and dried using natural air as a control and stepwise oven drying (12 min total with 3 min at each oven temperature in the order of 446 °F, 428 °F, 410 °F, and 392 °F). Instant rice quality parameters (rehydration and volume expansion ratio, and color-L* value) were analyzed. Long-grain cultivars had higher rehydration ratios and lower color-L* values than medium-grain cultivars. Stepwise oven-dried parboiled instant rice had a higher rehydration ratio than that dried using the control method of natural air. The highest MC levels (harvest) had the lowest rehydration ratios, which advocates for using lower MC rice to generate parboiled instant rice. The volume expansion ratio did not significantly differ for most of the studied factors and levels. More work needs to be done to include more quality parameters such as bulk density, texture, water activity, and protein content in order to increase the significance of trends discovered in this study. [ABSTRACT FROM AUTHOR]