Objective: The aim of this study was to investigate the amblyopia frequencies and types in children with refraction error or strabismus. Material and Method: In this cross-sectional and hospital-based study, 537 (51.5%) females and 506 (48.5%) males who were between 4-12 ages and totally 1043 cases with refraction error or strabismus were evaluated prospectively. All the patients underwent full ophthalmological examination. Amblyopia type, lateralization and its severity were documented for each patient diagnosed with ambliyopia. Results: Amblyopia was detected unilaterally in 98 (44.3%) cases, bilaterally in 123 (55.7%) cases, totally in 221 (21.2%) cases who were included in the study. The mean age was 8.6±2.47 (4-12) years. There was no statistically significant difference in the amblyopia frequency when it was compared between the male and female patients (x2=2.89,p=0.089). When bilateral and unilateral amblyopia were compared according to the amblyopia deepness, deep amblyopia was found to be higher in the unilateral amblyopia (x2= 8.88, p=0.012). When the patients were evaluated according to the amblyopia types; 158 (71.5%) refractive, 8 (3.6%) strabismic, 11 (5%) deprivation and 44 (19.9%) mixt refractive and strabismic ambliyopia were documented. When the amblyopia types were assessed according to the amblyopia deepness (x2=42.89,p=0.001), the frequency of deep amblyopia (81.8%) was found to be statistically higher in the deprivation amblyopia type. The types of refraction errors had no statistically significant impact on ambliyopia deepness in the patients with amblyopia (x2=2.37 p=0.668). Conclusion: In this study, we found high frequency of amblyopia in the patients with refraction error or strabismus. Since ambliyopia is considered as a preventable and treatable disease, it is obvious that a nation-wide eye screening program is needed in our country.