In this paper, we propose a mobile robot localiza- tion system in frequent GPS-denied situations. We utilize multi- ple observations that are obtained from sequential appearance- based place recognition and GPS. Using GPS observations has still some challenging problems such as multipath or signal lost under environments where there are tall buildings nearby. The appearance-based place recognition that is combined with positional information has capability to overcome the issue. Nevertheless, GPS observations which are obtained in the situ- ation sometimes have better quality (e.g. Precision or accuracy) than positional information from the place recognition because those coordinates always have some errors. We apply both of observations to a mobile robot localization for the sake of achieving robust localization. Moreover sequential appearance- based place recognition makes it possible to recognize their own position even when we navigate a robot at night. Our system uses not only multiple observations but also dead reckoning with the gyrodometry model. Our experiments are performed over aggregate 5300 m trajectory approximately that contains three times trials through a 1600 m ou