The modulation with different power of data and pilot channels will be used in the next generation of global navigation satellite systems. However, the traditional acquisition algorithms are mostly designed with equal-weighted coefficient of data and pilot channels. When the power of data and pilot channels is not equal, the traditional algorithms are not suitable for optimizing the performance. A power-weighted combining acquisition algorithm, which uses the different weighted coefficients for data and pilot channels, was proposed. The Least-Square fitting method was used to optimize the coefficients. The detection and false-alarm probabilities were derived with characteristic function of decision variable. The simulations prove that the acquisition threshold of the algorithm is improved by 0.4 dB when the power ratio of data and pilot channels is 1 ∶3, and the detection and false-alarm probabilities are 0.8 and 10^-3 respectively.