Abstract: Neutral Hydrogen (HI) intensity mapping survey provides a new way to probe the underlying dark matter distribution and it has been test with Green Bank Telescope (GBT) nbsp;and Parkes Telescope.  A new generation of radio telescope will enter operation in the next few years and present a unique opportunity to probe the Universe with large and deep sky survey. Now MeerKAT telescopes are built.  We proposed a new HI Intensity; mapping survey project with MeerKAT, known as MeerKLASS (MeerKAT Large Area Synoptic Survey). I will talk about the possible MeerKLASS science topics and the 1/f noise analysis with our testing data.