On aging, spatial memory declines to some degree in both, rodents and humans. It is unknown, however, whether aging brings about a decline of encoding and retrieval of spatial information in parallel. The present study examined spatial encoding and retrieval in male CD-1 mice at 4, 9, and 12 months of age in a complex dry-land maze. The total time to reach the goal zone was age-dependent favoring mice at 4 months of age. We showed previously that moving time represents encoding of spatial information and resting time represents recall of previously learned spatial information. The average moving time decreased from 69.8 ± 5.3 s (mean ± SEM), 69.7 ± 8.0 s, and 78.9 ± 4.9 s to 17.0 ± 2.3 s (p < 0.001 ), 24.7 ± 2.7 s (p < 0.001), and 31.0 ± 3.5 s (p < 0.001) at 4, 9, and 12 months of age, respectively. The average resting time decreased from 34.9 ± 5.6 s, 22.2 ± 4.2 s, and 41.7 ± 5.3 s to 3.6 ± 1.2 s (p < 0.001), 5.3 ± 1.8 s (p = 0.009), and 22.7 ± 4.9 s (p = 0.007) at 4, 9, and 12 months of age, respectively. We conclude that age-related deficits of spatial memory in mice manifest with an encoding deficit prior to a retrieval deficit.