Avoidance is regarded as an important feature for the development and maintenance of obsessive-compulsive disorder (OCD) and is usually assessed using explicit measures such as self-report scales. However, some behavioral schemata are unavailable to introspection, making them partially inaccessible by explicit measures. We used an approach-avoidance task (AAT) as an implicit measure to examine behavioral tendencies in patients with OCD, including patients with checking- and contamination-related symptoms (n = 63), compared with a healthy control group (n = 30). Participants were asked to respond to the color of a stimulus or stimulus frame by pulling a joystick toward themselves or by pushing it away. The stimuli were comprised of checking-related, contamination-related, and neutral pictures and words. Patients with contamination-related symptoms were slower when responding to OCD-related stimuli, independent of approach or avoidance. Unexpectedly, patients with checking-related symptoms were faster at pulling (approaching) and slower at pushing (avoiding) checking-related material compared with neutral stimuli. The slower pushing (avoiding) of checking-related compared with neutral material correlated positively with explicit ratings of avoidance. These results suggest a biased approach-avoidance tendency in patients with checking-related symptoms of OCD, but not in those with contamination-related symptoms of OCD. Future studies are necessary to assess whether the AAT might be useful in the assessment of treatment gains as well as whether it might be a training tool to enhance psychotherapeutic changes in OCD.