<p>The permeable nozzle has considerable potential for propulsion performance improvement and structural weight reduction. However, as a recently proposed thrust compensation nozzle, its optimization research is insufficient. The present work optimizes the expansion ratio of the permeable section starting position, the thickness of the permeable section wall, and the length of the expansion section using the NSGA-II multi-objective genetic algorithm, with altitude-averaged specific impulse and expansion section mass as optimization objectives. The optimization results show that the altitude-averaged specific impulse and expansion section mass have mutual exclusivity. When only thrust performance is considered, compared to the conventional nozzle with fixed expansion ratio, the optimal permeable nozzle has an 8% improvement in altitude-averaged specific impulse. The non-adaptive thrust loss of the permeable nozzle optimized for altitude-averaged specific impulse is reduced by 64.51% compared to the conventional nozzle with fixed expansion ratio. When both thrust performance and expansion section mass are considered, the permeable nozzle with its best compromise solution has a 7.3% improvement in altitude-averaged specific impulse and a 24.8% reduction in expansion section mass. The response surface methodology is employed at the 5&#xa0;km operating altitude to explore the intrinsic relationships between structural parameters, thrust performance, and flow field characteristics of permeable nozzles, and introducing the effective gas expansion area ratio for evaluating the compensation effect of the permeable nozzle.</p>