Introduction: Biochemical debridement with an irrigating solution is indispensable to remove microorganisms, debris flushing, and smear layer from a passage of the root canal, thus involving the use of many irrigants. Along with the desirable effects, these agents may have some detrimental effects on dental hard tissues. Aim and objective: To evaluate the effect of different irrigating solutions on the microhardness of radicular dentin of primary teeth. Materials and methods: Thirty buccolingual sections of roots of primary teeth (decoronated using a diamond disk mounted in acrylic) were indiscriminately distributed among three groups of 10 specimens, respectively, in accordance with the irrigants used, i.e., group I [1% sodium hypochlorite with 10% ethylene diamine tetraacetic acid (EDTA)], group II [6% citric acid (CA)], and group III (normal saline). Dentin microhardness was measured before and after irrigation at apical, middle, cervical levels of the roots with a Vickers indenter machine. Data so collected were analyzed using SPSS software version 24. Results: There was a statistically significant difference in the microhardness values of radicular dentin before and after irrigation with the different agents. More reduction was seen with the CA (24.62 ± 6.43) group when compared with 1% sodium hypochlorite with 10% EDTA group (33.09 ± 6.93) (p = 0.001). Conclusion: Citric acid, although an acid belonging to the organic category, acts as a chelating agent like that of EDTA, thus bringing about a significant reduction in microhardness of radicular dentin in primary teeth.