  Virtual Observatory (VO) is a collection of interoperating data archives and
software tools. Taking advantages of the latest information technologies, it
aims to provide a data-intensively online research environment for astronomers
all around the world.
  A large number of high-qualified astronomical software packages and libraries
are powerful and easy of use, and have been widely used by astronomers for many
years. Integrating those toolkits into the VO system is a necessary and
important task for the VO developers.
  VO architecture greatly depends on Grid and Web services, consequently the
general VO integration route is "Java Ready - Grid Ready - VO Ready". In the
paper, we discuss the importance of VO integration for existing toolkits and
discuss the possible solutions. We introduce two efforts in the field from
China-VO project, "gImageMagick" and " Galactic abundance gradients statistical
research under grid environment". We also discuss what additional work should
be done to convert Grid service to VO service.
