Many studies have demonstrated that culture has many effects on our behavior and thinking. In the field of basic visual processing, however, researchers have believed that our processing is universal; that all people see objects in the same way. Some recent studies have indicated cultural differences in visual processing, but others have not. Therefore, it is still controversial whether posteriori factors such as culture and visual environments affect basic perception/cognition or not. Possibly, this discrepancy occurs because the complexity of the experimental tasks draws upon high-level factors that could obscure cultural and environmental effects. Hence, to definitively assess the generality of cultural differences in perception, what is needed are simple tasks that use simple stimuli. To achieve this goal, we examined cultural differences in visual search for geometric figures, a relatively simple task for which the underlying mechanisms are reasonably well known. In the experiment, Japanese and North American participants were asked to search for the longer/shorter line among shorter/longer lines, and we successfully replicated earlier results: North American participants showed a reliable search asymmetry, with faster search for long among short lines than vice versa. However, Japanese participants showed no asymmetry. This difference did not appear to be affected by stimulus density. If the cultural difference in search is based exclusively on a differential engagement of strategic factors such as analytic/holistic processing, it should be invariant across different kinds of stimuli. However, other kinds of stimuli resulted in other patterns of asymmetry differences, suggesting that the cultural differences are not due to strategic factors, but are based instead on the target-detection process. In particular, our results indicate that at least some cultural differences reflect different ways of processing early-level features, possibly in response to environmental factors.