OBJECTIVES: To evaluate physician’s knowledge and adherence to asthma guideline adherence (GINA 2011) at emergency department of Hospital Pulau Pinang, Malaysia and to calculate cost of adhered and non-adhered prescriptions METHODS: A cross-sectional survey was conducted to evaluate knowledge of GINA, 2011 asthma guideline at emergency department of Hospital Pulau Pinang, Malaysia.  A total of 810 patient prescriptions of 27 doctors (30 prescriptions per doctor) were viewed to asses doctor’s guideline adherence. Patients’ prescriptions were categorised in terms of asthma severity as mild, moderate and severe. Prescriptions were labelled as adhered or non-adhered in terms of doctor treatment according to patient asthma severity as recommended by CPG (GINA 2011). Cost of adhered and non-adhered was calculated according to asthma severity. RESULTS: Twenty two (81.5%) doctor’s had adequate GINA, 2011 asthma guideline knowledge (Mean 16.7, SD ± 1.5). Six hundred and twenty eight (77.5%) patients received guideline (GINA 2011) adhered pharmacotherapy. Six hundred and seventy eight (83.7%) patients asthma were classified as mild asthma, 128 (15.8%) patients were classified as moderate asthma and 4 (0.5%) patients were classified as severe asthma. Pearson correlation indicated no statistical significant association between asthma guideline adherence and asthma guideline knowledge score (p=0.27).Univariate analysis indicate that patients with age group 25-35 years and with hypertension as co-morbidity received significantly better pharmacotherapy (p=0.04, p=0.03 respectively). Total cost of 628 adhered prescriptions was RM 5792.87 whereas cost of 182 non-adhered prescriptions was RM 1759.09. Cost of single mild asthma adhered prescription (RM 9.18) was less as compared to non adhered mild asthma prescription (RM 10.39).  CONCLUSIONS: Emergency doctor’s had adequate GINA, 2011 asthma guideline knowledge. Majority of patients received GINA, 2011 asthma guideline adhered pharmacotherapy. Cost effective medication can significantly reduce socioeconomic burden related to asthma.