Exclusive breastfeeding is an important thing at infant fince born. It is because breastmilk consilt of some substances that able to support the growth of infants. The substances are taurine, FADS2 (flavin adenine dinucleotide), (arachidonic acid) and DHA (Decosahexonoic Acid) that influence with the level of development of infant sensory reaction. However, not only internal factors (nutrition) but  also external factors (stimulation) are improving infant growth.

This study aims to determine the baby sensory reactions to the environment by given exclusive breastfeeding in Bee Creative Day Care Sambikerep Surabaya. This research uses descriptive qualitative research. Data collection techniques used were observation, interviews and documentation. The observations were conducted by observing and recording the development of infant sensory reactions through the stimuli. The interviews were conducted with caregivers, owners of day care, and parents about the infant nutritional need, the development of infant sensory reactions, nutritional care systems and health programs which was help by Bee Creative Day Care Sambikerep Surabaya. Documentation obtained in the form of baby's identity, caregivers, parents, schedule of daily activities, reports development of the baby, the baby's weight reports and photos of activities.

The results of the research from the benefits of giving exclusive breastfeeding in stimulating the infant reaction showed that every level of age has different level of achievment. At age 4 months babies are able to lend a hand to ask (hugged, held, or lap), accompanied by the stimulus. The infants who was aged 5 months were able to lend a hand to ask without a given stimulus. While, for the infants who was aged 6 months showed the infant was able to observe objects with a shaked and then dropped, repeatedly dropped objects if the object did not changed, searching for the source of the sound when he heard a voice / sound.

Keywords: ASI, the stimulus, the sensory reactions