An optical fiber temperature and pressure simultaneous measurement system based on wavelength scanning laser was proposed. The fiber optic sensor head is fiber Bragg gratings based on side hole polarization maintaining fibers. Taking use of its unique double reflection peaks arising from birefringence, simultaneous measurement of temperature and pressure can be acheived. Embedded technology was applied in the system. The controls of laser wavelength scanning, acquisitions of spectral data and the data demodulations based on Newton least squares fitting algorithm, were highly integrated in one system, greatly reducing the size and cost of the fiber optic sensing system. Experimental results show that the double reflection peaks correspond to changes in temperature and pressure with a good linear characteristics, in the temperature range of 10~50 ℃ and the pressure range of 0~1.2 MPa. The wavelength demodulation accuracy of the system is up to 1 pm, corresponding to the resolution of temperature and pressure is up to 0.1 ℃ and 0.1 MPa, respectively. The proposed system can provide a low cost, small size, reliable system solutions to the simultaneous measurements of temperature and pressure.