Purpose: The association between language delay and behavior problems in toddlers was examined in 2 studies, 1 conducted in a developmental clinic in New Jersey (Study 1; N = 83) and the other conducted in a developmental clinic in New York (Study 2; N = 103). Method: In both clinics, parents of 18- to 35-month-olds completed the Language Development Survey (LDS) and the Child Behavior Checklist/1.5-5 (CBCL). In Study 2, the Preschool Language Scale-Fourth Edition (PLS-4) was also administered. Neurodevelopmental delay (ND) and pervasive developmental disorder (PDD) symptoms were also assessed in both studies but were done so using different measures. Results: In Study 1, LDS Vocabulary score and CBCL Total Problems, Internalizing, and Withdrawn scores were significantly correlated. However, when children with ND and/or suspected PDD were excluded, only the correlation between LDS Vocabulary and Withdrawn remained significant. In Study 2, only the correlation between LDS Vocabulary and Withdrawn approached significance. Children delayed in language on the PLS-4 had higher CBCL scores than typically developing toddlers only on the CBCL Withdrawn syndrome. Conclusion: Significant associations between language delays and behavior problems were not found in 2 samples of 18- to 35-month-olds when children with ND and PDD were excluded, except that toddlers with language delays appeared to show elevated social withdrawal relative to typically developing toddlers.