Coordination of organ growth during development is required to generate fit individuals with fixed proportions. We recently identified Drosophila Dilp8 as a key hormone in coupling organ growth with animal maturation. In addition, dilp8 mutant flies exhibit elevated fluctuating asymmetry (FA) demonstrating a function for Dilp8 in ensuring developmental stability. The signals regulating Dilp8 activity during normal development are not yet known. Here, we show that the transcriptional co-activators of the Hippo (Hpo) pathway, Yorkie (Yki, YAP/TAZ) and its DNA-binding partner Scalloped (Sd), directly regulate dilp8 expression through a Hpo-responsive element (HRE) in the dilp8 promoter. We further demonstrate that mutation of the HRE by genome-editing results in animals with increased FA, thereby mimicking full dilp8 loss of function. Therefore, our results indicate that growth coordination of organs is connected to their growth status through a feedback loop involving Hpo and Dilp8 signalling pathways.