Abstract: The macro quarterly data from 2003 to 2019 was used to construct a vector autoregressive(TVP-SV-VAR)model by time-varying parameters with random fluctuations, and the impact of monetary policy uncertainty on macro-economics in different economic situations was empirically examined. The research results show that:during the upward phase of the economic cycle, the uncertainty of monetary policy had a positive effect on investment, consumption, economic output and price levels; during the downward phase of the economic cycle, the uncertainty of monetary policy had a negative effect on investment, consumption and economic output, and the impact on price levels remained positive but the intensity of the impact was significantly reduced. Monetary policy uncertainty had an asymmetric effect on macro-economy. In terms of impact time, the impact of monetary policy uncertainty on price levels was relatively short, and the impact on investment, consumption, and economic output persisted in the medium and long term. The monetary policy uncertainty weakened the effectiveness of monetary policy itself in counter-cyclical macroeconomic regulation. Therefore, the central bank should pay attention to the rhythm of monetary policy adjustment, reduce the degree of monetary policy uncertainty, and ensure the effectiveness of monetary policy regulation.