The present work examines the influence of dispositional personal belief in a just world (BJW) on (dis)honest behavior and the moderating role of just-world threats. Assuming a positive link between personal BJW and striving for justice and sensitivity to injustice, we first expected dishonesty to be negatively linked to higher levels of personal BJW. Second, assuming just-world threats to promote behavior that helps to re-establish the BJW, and considering honesty to be a matter of justice, we expected dishonest behavior to be lower after just-world threat. Due to a higher sensitivity to injustice, this should be the case especially for people who boast a high personal BJW. In two studies, we assessed participants' dispositional personal (and general) BJW and manipulated just-world threat. Afterwards, we assessed dishonesty by using a dice task (Study 1, N = 135), or an anagram task (Study 2, N = 147), respectively. In both studies, higher levels of personal BJW were negatively linked to dishonesty. Additionally, in Study 1, participants in the high (vs. low) threat condition showed less dishonesty, especially when having a high personal BJW. Results of Study 2 did not support this idea. In both studies, general BJW did not predict dishonesty.