Study objective: The aim of this study was to determine the effect of supportive - educational program on the anxiety and satisfaction of mothers of children undergoing Lumbar puncture. Design: This study was a semi-experimental clinical trial, with two groups (intervention and control), pre-posttest design, and single not-blind. Sample size: This study was conducted on 60 children’s mothers (30 mothers per each group) hospitalized in pediatric emergency department of Quaem, Dr Sheikh, and Imam Reza hospitals of Mashhad. The main outcome variables in this study included: Anxiety and satisfaction. Inclusion criteria: Mother's age between 18 years to 55 years old; not experienced major stressors (such as divorce) within 6 month before; lack of sedatives and anti-anxiety drugs within 2 days before the test, and children's age between 1 month to 14 years old. Exclusion criteria: Children required emergency lumbar puncture test and, lack of cooperation mother to participate in the post test. Sampling was conducted via convenience sampling method, at the beginning of sampling; in order to avoid from information distribution between two groups, the first group was selected by a simple draw, and the intervention group was selected as first group. The mothers in the experimental group received an educational-supportive program (that included: Informational and emotional supports for 70 minutes), and an information booklet. The control group did not receive any intervention. Data were collected by demographic and spielburger questionnaires. The anxiety level was measured before and after the intervention (immediately before the LP) in two groups. Also, the satisfaction of mothers from preparation before the lumbar puncture test in their children were measured by the researcher-made questionnaire at 3 hours after Lumbar puncture test in two groups.