Outage probabilities in shadow fading channels of high-speed railway (HSR) sce- narios are evaluated when macro-diversity and micro-diversity techniques are considered. First, the power density function of signal-to-noise ratio (SNR) is derived in order to obtain a close form of outage probability for the narrow-strip-shaped cells in HSR. It is noteworthy that a Rice distribution is more realistic for modeling small-scale fading in HSR environments, a log-normal distribution is adopted to model the shadowing component. Then, the outage probabilities on the assumption of micro-diversity with maximal ratio combining and macro-diversity with selection combining are deduced, considering correlation property of shadow fading among base stations. It is calculated as a function of the shadowing cross-correlation coefficient, which is defined as correlations of links between one mobile station and two different base stations. Finally, the attenuation of signal amplitude caused by carriage passing loss in outage analysis for HSR is investigated.