The aim of this study was to determine the psychometric properties and to derive norms for the Omani version, Of the Otis-Lennon Mental Ability Test (OLMAT), Elementary Level, Form (K), in The Muscat region. This Level is one of the six levels in (OLMAT) series, and consists of (80) items. After the test was modified, The Omani version was administered to a random sample of (726) students: (373) male and (353) female, from grades (2,3,and 4) elementary Level from Muscat region of the Sultanate. The following test validity indices were obtained: Content Validity, Criterion Validity and Construct Validity. The reliability of the test was obtained by three methods: Test-Retest, Split-Half and Cronbach alpha formula. All the values of validity and reliability indices were statistically significant at (a=0.05) level. Norms were derived by administering the test to (726) students from all grades and age levels. Percentile Ranks, Stanines, Deviation IQs and Grade and Age Equivalent scores were developed from interbattery standard-score distributions for each chronological grade and age group. Some recommendations were suggested in light of the finding.