Abstract: Objective: This study aimed to evaluate the lethal efficacy of ultrasonic waves against Aedes albopictus larvae at different developmental stages under various exposure parameters (distance and duration), and to preliminarily investigate the influences of water body characteristics (size and depth) and ultrasonic device specifications, thereby providing experimental evidence for the application of ultrasonic mosquito control technology. Methods: Under controlled laboratory conditions, two commercially available ultrasonic devices (40 kHz/300 W and 50±5 kHz/70 W) were used to systematically examine the effects of exposure distance (20-100 cm), exposure duration (1-60 min), larval instar (I-II and III-IV), and water body type on the immediate mortality of Aedes albopictus larvae collected from urban areas of Shanghai. Statistical analysis was performed using the chi-square test. Results: Ultrasonic exposure exhibited lethal effects on larvae across all instars. For early-instar larvae, exposure duration significantly influenced mortality at all tested distances (20-100 cm) (χ² = 25.57-32.74, all P < 0.001). At short exposure durations (1 min and 3 min), distance had no significant effect (P > 0.05); however, beyond 6 min, distance became a significant factor (P < 0.05). Under identical exposure conditions, mortality rates were generally higher in I-II instar larvae compared to III-IV instar larvae, with this difference becoming more pronounced over extended exposure times. Mortality was jointly influenced by both time and distance, though the effect of time diminished at longer distances (100 cm). Preliminary experiments indicated that control efficacy was lower in shallow water than in deep water, and no significant difference in larval mortality was observed between the two ultrasonic devices with different frequencies and power outputs. Conclusion: Under laboratory conditions, ultrasound effectively kills Aedes albopictus larvae, with efficacy being modulated by larval instar, exposure distance, and aquatic environment. Compact ultrasonic devices show potential for field application in biological mosquito control.