YBCO thin films on $SiO_2$/Si substrate were fabricated by spin-coaing of an alkoxide-derived precursor and heat treatment. The structural and electrical properties of the YBCO films were investigated as functions of annealing temperature at $600{sim}800^{circ}C$. Although YBCO single phase was not synthesized, dense films of YBCO matrix phase and minor second phases have been successfully fabricated at the annealing temperatures of $650{sim}800^{circ}C$. Thickness and temperature coefficient of resistance (TCR) of YBCO thin films with annealing temperature of $750^{circ}C$ were 0.31 ${mu}m$ and $-2.92%/^{circ}C$, respectively.