EIO Eaton Vance Ohio Municipal Bond Fund Common Shared of Befeficial Interest, $.01 Par Value

Eaton Vance Insured Ohio Municipal Bond Fund (AMEX:EIO) (the �Fund�), a closed-end management investment company, today announced the earnings of the Fund for the six months ended March 31, 2007. The Fund�s fiscal year ends on September 30, 2007. For the three months ended March 31, 2007, the Fund had net investment income of $605,387 ($0.241 per common share). From this amount, the Fund paid dividends on preferred shares of $178,955 equal to $0.071 for each common share), resulting in net investment income after the preferred dividends of $426,432, or $0.170 per common share. The Fund�s net investment income for the six months ended March 31, 2007 was $1,213,197 ($0.483 per common share, before deduction of the preferred share dividends totaling $0.145 per common share), resulting in net investment income after the preferred dividends of $0.338 per common share. In comparison, for the three months ended March 31, 2006, the Fund had net investment income of $614,156 ($0.245 per common share). From this amount, the Fund paid dividends on preferred shares of $158,130 equal to $0.063 for each common share), resulting in net investment income after the preferred dividends of $456,026, or $0.182 per common share. The Fund�s net investment income for the six months ended March 31, 2006 was $1,229,988 ($0.490 per common share, before deduction of the preferred share dividends totaling $0.119 per common share), resulting in net investment income after the preferred dividends of $0.371 per common share. Net realized and unrealized losses for the three months ended March 31, 2007 were $194,570 ($0.070 per common share). Net realized and unrealized gains for the six months ended March 31, 2007 were $327,973 ($0.138 per common share). In comparison, net realized and unrealized gains for the three months ended March 31, 2006 were $499,621 ($0.191 per common share). Net realized and unrealized gains for the six months ended March 31, 2006 were $359,295 ($0.135 per common share). On March 31, 2007, net assets of the Fund applicable to common shares were $38,864,950. The net asset value per common share on March 31, 2007 was $15.47 based on 2,512,727 common shares outstanding. In comparison, on March 31, 2006, net assets of the Fund applicable to common shares were $37,624,482. The net asset value per common share on March 31, 2006 was $14.97 based on 2,512,727 common shares outstanding. Common shares of the Fund are traded on the American Stock Exchange. The Fund is managed by Eaton Vance Management, a subsidiary of Eaton Vance Corp, which is listed on the New York Stock Exchange under the symbol EV. Eaton Vance and its affiliates had approximately $150.0 billion in assets under management on April 30, 2007. Eaton Vance Management will make available periodic summary information regarding portfolio investments. Those interested should call Eaton Vance at (800) 262-1122. EATON VANCE INSURED OHIO MUNICIPAL BOND FUND SUMMARY OF RESULTS OF OPERATIONS (in thousands, except per share amounts) � Three Months Ended Six Months Ended March 31, March 31, 2007� 2006� 2007� 2006� Net investment income $605� $614� $1,213� $1,230� Net realized and unrealized gains (losses) on investments ($195) $499� $328� $359� Preferred dividend paid from net investment income ($179) ($158) ($364) ($300) Net increase (decrease) in net assets from operations $231� $955� $1,177� $1,289� � Earnings per Share Outstanding Net investment income $0.241� $0.245� $0.483� $0.490� Net realized and unrealized gains (losses) on investments ($0.070) $0.191� $0.138� $0.135� Preferred dividend paid from net investment income ($0.071) ($0.063) ($0.145) ($0.119) Net increase (decrease) in net assets from operations $0.100� $0.373� $0.476� $0.506� � Net investment income $0.241� $0.245� $0.483� $0.490� Preferred dividend paid from net investment income ($0.071) ($0.063) ($0.145) ($0.119) Net investment income after preferred dividend $0.170� $0.182� $0.338� $0.371� � Net Asset Value at March 31, (Common Shares) Net assets (000) $38,865� $37,624� Shares outstanding (000) 2,513� 2,513� Net asset value per share outstanding $15.47� $14.97� � Market Value Summary (Common Shares) Market price on AMEX at March 31 $15.20� $14.73� High market price (six months ended March 31) $15.50� $15.00� Low market price (six months ended March 31) $14.32� $13.71�