The principal objective of this study was to verity the mother's knowledge, of children between zero and one year old, want to obtain to care their child. The author interviewed 110 primipara mothers, in health center, in São Paulo. The desirable knowledge, in decreasing sequence were nutrition, organic manifestation or common disease during childhood development of child corporal hygiene, growth, sleep, vaccination, emotional needs and environment hygiene. The author, obtained that mother of younger child needed more information. The results of this survey can be generalized with restriction because the individual needs must be considered.