The present study aimed to evaluate the effects of eyestalk ablation on feeding, gonad development, and energy conversion of Penaeus monodon broodstock. An experiment of 30 days was carried out on broodstock (average body length 28.4 ± 0.95 cm, average body weight 96.7±6.48 g) with (treatment) or without eyestalk ablation (control), cultivated under a water temperature of 27.0±1.5 °C, salinity of 30–32, pH of 8.0–8.3, and light intensity of 1000 lx. Results showed that food consumption and feeding intensity of the eyestalk-ablated broodstock were higher than those without eyestalk ablation. The night-time feeding intensity was 1.46-fold and 1.31-fold higher than the daytime feeding intensity in the treatment and control groups, respectively (P<0.01). Food consumption in the treatment group increased continuously during sexual maturation acceleration, whereas that of the control group fluctuated. At the end of the experiment, the gonadosomatic index (GSI) increased by 607.14% and 100.00% in the treatment and control groups, respectively (P<0.01). The gonadal wet and dry mass ratio (Gd/m) was higher in the treatment group than those in the control group, but the difference was not significant (P>0.05). Furthermore, the body energy values (Eb) slightly decreased in both groups. The increase in the gonad energy value (Eg) was significantly higher in the treatment than control group (P<0.01). Thus, the broodstock showed negative growth in their breeding season from the perspective of body energy value. During the experimental period, food conversion efficiency (FCE) and energy conversion efficiency (ECE) values of the treatment group were significantly higher than those of the control, with FCE values of 11.06% and 1.89%, respectively, and ECE values of 15.45% and 2.64%, respectively. These results indicated that eyestalk ablation promoted food consumption, feeding intensity, gonad development, and energy conversion efficiency of P. monodon broodstock. During gonad development, food was the chief, though not the only, source of energy, with tissues and organs also important energy suppliers. The results of the present study will hopefully improve our understanding on the characteristics of feeding, gonad development, and energy conversion of P. monodon broodstock during their breeding season, and provide a theoretical foundation for the scientific cultivation of P. monodon broodstock.