A cross-sectional pilot study was conducted in acute leukemia adult patients in order to characterize oral mucosal conditions in acute leukemia, and to analyze their association with certain clinical, nutritional and laboratory parameters. Oral evaluation was performed. Epidemiologic, clinical and laboratory data were considered. Statistical analysis included non-parametric tests and multivariate analysis. A total of 30 patients (60% males) were included; median age of 39 (range 17-62) years old. The median percentage of caloric intake adequacy was 96.8% (range 21.8-205.7%), and the median ideal weight was 117.9% (range 88.2-162.9%). The most common oral mucosal findings were pallor and furred tongue. Leukoedema was seen only in patients <30 years old [OR=1.9 (CI=1.1-3.1); p=0.003]; more cases of fissured tongue [OR=17.1 (CI=1.8-163.8); p=0.005] were seen in subjects >30 years old. Exfoliative cheilitis was more frequent in females [OR=2.7 (CI=1.2-6.1); p=0.02] and in patients with high β-carotene concentrations [Md= 94.5 vs 57.0 µg/dl; (p=0.01)]. Higher rates of diffuse hyperpigmentation were seen (p<0.05) in patients having low vitamin B12 [Me=240 vs 626 pg/ml] and folic acid concentrations [Md=5.8 vs 8.5 ng/ml]; Geographic tongue was found among patients with low serum albumin [Md= 2.7 vs 3.5 g/dl; (p=0.006)] and folic acid [Md=7.9 vs 11.6 ng/mL; (p=0.02)]. Furred tongue was more frequent in patients with low hemoglobin concentration [Md=7.2 vs 8.5 g/dl ;( p=0.01)] and poor oral hygiene [Md=1.1vs 0.7 ;( p=0.04)]. Nutritional depletion was more frequently observed among patients with indentation (p=0.04) and geographic tongue (p=0.03)]. Age, gender and certain micronutrient deficiencies were significantly associated to specific oral mucosal findings in acute leukemia.