People rely on reputational information communicated via gossip when deciding about with whom to cooperate, whom to believe, and whom to trust. In two studies, we investigated whether 5- and 7-year-old children trust in gossip when determining a course of action. In Study 1, 5- and 7-year-old German-speaking peer dyads (N = 64 dyads, 32 female dyads) were presented with a collaborative problem-solving task (e.g., deciding together what a creature eats). Each child individually received conflicting information about the solution from a different informant (e.g., one proposed rocks; the other proposed sand). Each child additionally heard gossip about the informant's reputation: one informant had a good reputation; the other had a bad reputation. In the experimental condition, the reputation was relevant to the task (honesty), whereas it was irrelevant in the control condition (tidiness). Seven-year-old dyads, and 5-year-old dyads to a lesser extent, settled on the items suggested by the informant with good reputation in the experimental but not in the control condition. Only 7-year-old children explicitly referred to the information conveyed via gossip, engaging in metatalk about the reputations of the informants. In Study 2, we replicated these findings in a more controlled experiment in which 5- and 7-year-old American English-speaking children (N = 48, 27 girls) tried to convince an adult partner who proposed the item suggested by the informant with bad reputation. Thus, starting around age 5, and more reliably at age 7, children selectively rely on gossip in identifying trustworthy individuals in their collaborative reasoning with partners.