We determined the minimal insertion lengths for appropriate placement of orogastric tubes in very low birth weight infants (< 1500 gm). Feeding tubes marked in centimeter increments were placed orogastrically by using standard neonatal intensive care unit protocol. When radiographs were taken, the centimeter marking at the lip was recorded, and an investigator blinded to the recorded measurement scored the orogastric tube position on radiograph as high (too short), low (too far), or adequate. Data were collected until measurements were available for at least five separate infants for each 250 gm interval of birth weight < 1500 gm. A total of 188 radiographs in 31 consecutive, appropriately grown, very low birth weight infants were reviewed. Seventeen (9%) could not be interpreted because of radiographic technique or because the tip of the orogastric tube was not visible. Of the 171 radiographs suitable for review, the orogastric tube position was low in 8 (5%), high in 57 (33%), and in adequate position in 106 (62%). When data were stratified according to weight groups, minimum insertion lengths were identified, and provided clear and statistically significant separation for orogastric tubes positioned adequately versus those positioned high. The number of orogastric tubes positioned low was too small to provide meaningful information. This information was then used prospectively to assist in orogastric tube(s) position, with a subsequent increase in the percentage of orogastric tubes positioned adequately to 86%. This study confirms that there are minimum orogastric tube insertion lengths required for adequate intragastric positioning. Paying attention to this information can decrease the number of orogastric tubes that are positioned in the esophagus.