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We have detected the infrared spectrum of the HOCO radical in the $C=O$ stretching region around $1850cm-1$. The radical was formed by excimer laser photolysis of acetic acid $(CH3COOH)$ or acrylic acid $(C2H3COOH)$ at 193 nm and its infrared spectrum measured by diode laser absorption spectroscopy. The observed spectrum has the structure expected for a parallel, a-dipole, band as would be predicted based on the expected radical structure and by comparison with the analogous band of isoelectronic FCO. P, Q and R branch lines have been detected and the band origin lies slightly above $1850cm-1$ which compares with the $1843cm-1$ $reported1$ for the band in a low temperature argon matrix. The detailed assignment of the $Ka$ rotational structure in the spectrum is currently in progress and results will be reported at the meeting. When the spectrum is assigned, it should prove to be an ideal vehicle for measurement of chemical reaction rates on a state by state $basis.1$M. E. Jacox, J. Chem. Phys. 88, 4598-4607 (1988)