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Background & Objective: In all of world, a portion of household income expends on health care cost. Amount and distribution of the proportion indicate financial burden of health care in the societies. WHO believes that one of the main determinants in health system efficiency is fairness of financial contribution. This study aimed distribution pattern of urban households’ income, health expenditure by cost types and measuring of equality on health care costs in the Gorgan district. Materials & Methods: In order to establish the population laboratory, this cross-sectional study assessed 1014 household in the Gorgan health posts (No 4 and 8) on January 2003. health insurance status, monthly household income and monthly health care cost gathered through interviewing with the husbandmans. Results: Health insurance coverage was 67% in highest and 44% in lowest income deciles (P<0.05). Median and mean of assessed households’ income and household health care cost were 1200000 Rls, (1669669±187300 Rls) and 80000 Rls, (281530±95124 Rls) respectively. Mean of median of out of pocket proportion health care cost per households’ income was 0.57±0.03 and 0.66 respectively. 13% of total income expended health care cost through out of pocket. This proportion in highest and lowest income decile was 7% and 28% (P<0.05). Gini coefficient of health care cost and out of pocket cost per total household income were 0.22 and 0.18 respectively. Conclusion: Low income households expended almost 40% of their income in order to purchasing of health care, in comparison to richest households, they spent 9% of total income. Instead of, additive development of health insurance systems and complementary insurance mechanisms, a half of health care cost in the population spend by out of pocket. According to WHO standards of health system performance, revising health insurance system and payment mechanisms are mandatory.