Adsorption of oxygen on the Ag(110)1x1 surface is studied by field ion-scanning tunneling microscopy (FI-STM) and high resolution electron energy loss spectroscopy (HREELS). Linear chain (added-row) formation in the [001] direction upon oxygen adsorption is observed. The step movement and step bunching are observed at the exposure lower than 60 L. Another type of chain formation are observed between the added rows with the local 3X1 configuration. The coverage and time-dependent HREELS data shows rather complicated dynamics in the case of room temperature adsorption. The HREELS data with the resolution of 4 meV (FWHM) shows an extra broad, weak peak at 15 meV, which has a maximum peak value at the exposure near 1800 L corresponding to the completion of the 3X1 phase.