The potential use of the Internet for apparel retail marketing is extremely viable (Murphy, 1998); however, most of the journal papers on apparel Internet shoppers are limited to the comparison of demographic, psychographic, and behavioral characteristics between shoppers and non-shoppers (McKinney, 2004). Little empirical research has addressed the role of impulsiveness in online apparel shopping behavior. In the past, impulse buying was considered as something bad and consumers felt guilty after impulse buying (Ainslie 1975; Levy 1976). However, most researchers now no longer view impulse buying as a negative phenomenon because studies showed that impulse buying satisfies a number of hedonic desires (Piron 1991; Rook & Fisher 1995; Thompson, Locander, & Pollio 1990). Impulse buyers exhibited greater feelings of amusement, delight, enthusiasm, and joy (Weinberg & Gottwald, 1982) and often felt uplifted or energized after a shopping experience that involves impulse buying (Rook, 1987; Gardner & Rook, 1988; 1993) because impulse buying can provide the enjoyment of novelty and surprise, and the ability of mood alteration (i.e., breaking out of negative mood state) (Gardner & Rook, 1988; Rook, 1987). Recognizing the positive feelings generated from impulse buying and considering the increasing frequency of college students'' Internet shopping (Seock, 2003), one strategy to create competitive advantages in the apparel market of college students is to understand the variables related to impulse buying and based on the understanding provide a website that generates pleasurable shopping. The purpose of this study was to examine the relationships between online apparel impulse buying behavior and apparel involvement, apparel website attributes, and product category/price. The data were collected using an online survey with a structured questionnaire. To recruit participants, 37,590 e-mails were sent to six universities located in different regions of the United States. A total of 687 college students responded to the survey including 284 online apparel buyers, 194 non-online apparel buyers, and 209 non-apparel website visitors. When the impulsiveness of online apparel purchases in general was used to divide the participants into impulse buyer and non-impulse buyer groups, the Chi-square test results showed that there were significantly more female respondents in the impulse buyer group than in the non-impulse buyer group. However, when impulsiveness of last purchase was used to divide the participants into impulse purchase and non-impulse purchase groups, the results showed no significant difference between the genders. For other results, the findings were all consistent. Respondents in the impulse buyer and purchase groups than the non-impulse buyer and purchase groups had a greater amount of total monthly income and spent more money on apparel products. The impulse buyer and purchase groups visited websites that sold clothing/accessories more frequently and purchased more apparel products online over the past six months than the non-impulse buyer and purchase groups. These results suggest that impulse buyers are an important segment of the apparel online market. Four hypotheses were put forward to test the relationships among the variables. Before the proposed hypotheses could be examined, the factor analysis was first conducted to determine the constructs of apparel involvement and website attributes. The results showed that apparel involvement consisted of three factors (i.e., sign value/perceived importance, pleasure value, risk importance/probability) and website attributes consisted of four factors (i.e., website design, product presentation, promotion, product search/policy information). The results of MANOVA showed that the impulse buyer group perceived the sign value/perceived importance and the pleasure value of apparel involvement significantly higher, and perceived the risk importance/probability of apparel involvement significantly lower than the non-impulse buyer group. Based on the results, H1 was supported. Impulsive and non-impulsive online apparel buyers differed significantly in their apparel involvement. For H2, the results indicated that the impulse purchase group evaluated the website where they bought the last apparel item significantly better in website design, product presentation, promotion, and product search/policy information than the non-impulse purchase group. Based on the results, H2 was supported. The evaluations of the attributes of websites where impulse purchases and non-impulse purchases of apparel products were made were significantly different. Test of H3 showed that some product categories purchased by the respondents in the impulse purchase group were significantly different from those bought by the non-impulse purchase group. Categories such as shirt/blouse and belt were bought more frequently by the respondents in the impulse purchase group whereas shoes were bought more frequently by those in the non-impulse purchase group. The respondents in the impulse purchase group bought more items that cost less than $25 than those in the non-impulse purchase group. Based on the results H3 was supported. The product categories purchased by the impulse purchase group and non-impulse purchase group were significantly different. The multiple regression results showed that the sign value/perceived importance of apparel involvement contributed the most in explaining impulsiveness of online apparel buying behavior, followed by product price, risk importance/probability of apparel involvement, and product presentation of website attributes. Other factors, such as the pleasure value of apparel involvement and website attributes in website design, promotion, and product search/policy information, had no significant linear relationships with the impulsiveness of online apparel buying behavior. Based on the results, H4 was partially supported. From the results of the present study, it is concluded that apparel involvement, website attributes, and product price are closely related to the impulsiveness of consumers'' online apparel buying behavior. This study is beneficial to researchers and marketers by identifying possible psychological reasons for impulse buying as well as suggesting strategies to develop an apparel website that facilitate impulse buying behavior. / Ph. D.