Parascaris sp. is the largest nematode parasite of equids and is responsible for colic and death in foals through intestinal obstruction. Parasite control largely relies on the use of anthelmintics including ivermectin and moxidectin that act on glutamate‐gated chloride channels (GluCls). However, Parascaris sp. resistance to macrocyclic lactones is a growing issue over the recent years throughout the world. Moreover, the GluCls of Parascaris sp. targeted by macrocyclic lactones are unknown. Here we identified and cloned the cDNAs of Peq‐avr‐14b and Peq‐glc‐2 encoding two GluCl subunits and investigated them at the functional level. The subunits Peq‐AVR‐14b and Peq‐GLC‐2 were expressed singly and in combination in Xenopus laevis oocytes to explore their function and pharmacology. Two‐electrode voltage clamp recordings showed that each subunit could not form an homomeric channel. Interestingly, we have found that the coexpression of Peq‐AVR‐14b and Peq‐GLC‐2 led to a novel functional GluCl subtype. Moreover, we demonstrated that moxidectin and ivermectin were more potent agonists than glutamate. We also detected a SNP in the Peq‐avr‐14b gene from ivermectin‐resistant worms that may encode a truncated form of the subunit. Its functional relevance in ivermectin resistance is in progress. Here we report the functional characterisation of the first moxidectin/ivermectin‐sensitive GluCl of Parascaris sp., thus opening the way for better understanding the mode of action of macrocyclic lactones and resistance mechanisms in ascarids.