CD1d is an unique antigen presenting molecule which provides antigenic repertoires to NKT cells. To examine molecules required for CD1d antigen presentation, we determined an interaction between CD1d and several endoplasmic reticulum (ER) resident molecular chaperones by co-immunoprecipitation. Results indicated that calnexin and calreticulin seem to be bound to mouse CD1d, but TAP and tapasin do not bind. Further, we screened an yeat two hybrid system to identify proteins that help mouse CD1d transportation in the cytosol. We found that two proteins, heat shock protein a sub-unit $(Hsp90{alpha})$ and protein kinase C and casein kinase substrate in neurons 3 (PACSIN-3), interact with CD1d. Future study will be focus on the role of these molecules during the CD1d antigen presentation.