Many digital libraries are providing Virtual Reference Services (VRS). There could be various approaches to increase the quality of VRS. In this study, we focused on two key factors; improving helpfulness and reducing user's feeling of intrusiveness. Studies indicated that librarian-initiated attempts for help may increase user's feeling of intrusiveness [2] [3]. It is challenging to provide high helpfulness along with less intrusiveness in VRS. This study aimed to identify factors that contribute to improving helpfulness and reducing intrusiveness. Data were collected based on a survey using systemic random sample approach. Our initial results indicated that awareness, timing, and transparency were key factors affecting the helpfulness and intrusiveness.