Behavioral modification through training is an important part of the owner-pet bond and highly impacts the quality of this relationship. The effect of long-chain polyunsaturated fatty acid (LCPUFA) supplementation on cognitive function was studied in five litters of puppies. From 3 weeks of age, half of each litter was supplemented with LCPUFA (docosahexaenoic acid as 1% and arachidonic acid as 2% of total fat intake) or a placebo (corn oil as 2% of total fat intake), with 20 puppies included in each treatment group. Tests for mental stability (cry and shriek test), problem solving (U maze and long maze), memory (long maze), and cue association (T maze) were performed at standard ages between 8 and 16 weeks. Differences between treatment groups for each response were tested by nonparametric analysis of variance of ranked data after accounting for differences in litters within treatment groups. No significant difference was found between treatment groups for either cry and shriek times or time to run the U maze. No differences were found for the first trial in the long maze. On the second trial, the mean, median, and minimum run times were significantly lower (P <.05) for the LCPUFA-treated puppies. The median and minimum numbers of errors were directionally (P <.10) lower for the LCPUFA-treated puppies in the long maze. There were no significant differences in run time or errors between treatment groups for the T-maze tests. LCPUFA significantly enhanced memory in puppies, as shown by response differences in the long maze. The significant improvement in memory observed in LCPUFA-fed puppies may enhance trainability and support an improved pet-owner relationship.