Marine protected areas (MPAs) help manage marine ecosystem stressors, with no-take MPAs boosting target species' density, size, and biomass. Benthic species like lobsters, which have high site fidelity, benefit significantly from such protections. This study assessed the effects of MPAs on rock lobster Jasus edwardsii in southeastern Australia. From 2013 to 2023, we sampled over 2,000 lobsters using 1,040 baited pots (590 inside MPAs, 450 outside). Lobster abundance and size were higher inside MPAs (3.05 individuals/pot, 127 mm average length) than outside (1.4 individuals/pot, 121 mm). We used species distribution models to account for habitat and environmental variability when assessing protection effects, incorporating factors like depth, seafloor complexity, temperature, and wave energy. These models explained 18%–75% of the variability, with predictive accuracy between 45%–86%. Lobster counts, sizes, and biomass responded positively to MPA protection despite regional differences. Depth, fishing region, and MPA zone were key predictors, while other factors had variable effects. Our findings underscore MPAs' role in biodiversity conservation and their potential to support local fisheries, with benefits likely extending beyond protected areas.