This paper describes an approach to extract the aspectual information of Japanese verb phrases from a monolingual corpus. We classify Verbs into six categories by means of the aspectual features which are defined on the basis of the possibility of co-occurrence with aspectual forms and adverbs. A unique category could be identified for 96% of the target verbs. To evaluate the result of the experiment, we examined the meaning of -leiru which is one of the most fundamental aspectual markers in Japanese, and obtained the correct recognition score of 71% for the 200 sentences.