The objective of this study was evaluate the effect of soil management systems and straw levels in flooded irrigated rice grain yield. The experimental design was a completely randomized with three experiments and 10 replications in experiment 1 and 2 and 6 replications in experiment 3. The experiments were: E1 - no-till system (E1PD) and conventional system with two harrowings at 0.0–0.07 m layer and leveling with remaplam (E1PC), after three years of rice cultivation, with sowing of ryegrass in winter and grazing; E2 - no-till system (E2PD) and conventional system after native field (E2PC); E3 - no-till without straw on soil surface (E30P), current straw on soil surface of 3,726 kg ha^-1 (E31P), two times current straw of 7,452 kg ha^-1 (E32P) and three times current straw of 11,178 kg ha^-1 (E33P). Were evaluated the average geometric diameter of aggregates, soil bulk density, soil porosity, macro and microporosity, in 0.0-0.05 and 0.05-0.10 m layer. At the harvest were evaluated the number of panicles in 0.25 m² area, number of filled, empty an total grains in 10 panicles, thousand grains weight and rice grains yield in 2 m². In the conventional system macroporosity and total porosity was greater than no-till system, however, this not results in differences in production components and rice grain yield. Rice straw levels in no-till up to 11,178 kg ha^-1, before sowing, not reduces flooded irrigated rice grains yield.