This paper analyzes the liquidity component of corporate bond spreads using a new illiquidity measure for corporate bonds in Korean bond market. We perform the empirical study during 2005~2012, which spans before and after global economic crisis exacerbated by the collapse of Lehman Brothers. At first, we estimated directly liquidity measure λ with four liquidity variables: Amihud measures of price impact, turnover, zero trading days, and the variability. Next, we regressed corporate bond spreads on λ after controlling for another explanatory variables within each rating before and after global economic crisis period. Lastly, we calculated the size of liquidity component to look directly at the impact of corporate bond illiquidity on corporate bond spreads. Through this study of liquidity component, we could compare the size of liquidity premium on corporate bond spreads within each rating, and maturity before and after global economic crisis period. As results, before andafter the global economic crisis period, the effect of illiquidity on spreads was positive and statistically significant for AA and A-rated bonds meanwhile only for AA-rated bonds during the period. The size of liquidity component has become bigger since the global economic crisis period and was peaked at A-rated bonds with 2- to 5-year maturities. Those results shows that the liquidity component is comprised of important parts of issuing price of A-rated bonds whose maturities at the time of issuance are mostly 3 to 5 years.