The invention provides an RNA analyzing method of paraffine section tissue. The analyzing method comprises the following steps of performing DNA degradation on the paraffine section tissue, and extracting RNA of samples; preparing a paraffine section sample nucleic acid library, and sequencing sample RNA; performing quality control on the sample data obtained by sequencing; comparing the sample data after quality control with a reference genome, and performing quality control on comparing results; and performing transcriptome assembling and transcript quantifying on the sample data after quality control of comparing results, and performing quantification analysis, gene difference expression analysis and fusion gene analysis on gene expression. The invention provides an index and detectionmethod for completely assessing RNA quality of the paraffine section tissue, so that RNA of the paraffine section tissue can be comprehensively assessed, and the assessment results are accurate and effective. An effective reference basis is provided for subsequent analysis accuracy.