ABSTRACT: A comparison of five independent measurements of the ocular diopiric components utilizing both ultrasonic 2nd photographic phakometric techniques was made on both eyes of twenty children under first non-cycloplegic and then one hour later, cycloplegic conditions. The variances for both the phakometric and ultrasonic measurements made under cycloplegia were not significantly different from those made in the undrugged state. Thus, the hypothesized improvement in reliability accomplisbed through the use of cycloplegia was not found experimentally. Both right and left eye ocular component values determined in the non-cycloplegic state were shown to have significantly higher validity than those for the cycloplegic state.