Lignin rich fermentative residues are abundantly available with growing number of fermentation plants over the globe as need of renewable energy sources like biohydrogen is increasing day by day. Fermentative residues offer significant potential for renewable chemicals and biofuel production, cellulosic content of biomass converted into biohydrogen in fermentation process but hemicellulose and lignin constitute the major portion of fermentative residues which hinders further biochemical conversion of this valuable resource. This study investigated the breakage of complex lignin structure and β-O-4 linkage with dilute acid and hydrothermal pretreatment for further biohydrogen production from lignin rich fermentative residues. Fermantative rasidual (FRs) were placed in autoclave reactor with 1-5% HCl and distilled water at 120 °C for 30-120 minutes and it was observed both pretreatment methods are effective in lignin valorization. 2% HCL was most effective with increasing concentration it inhibited the process and deteriorated the whole structure and decreased biohydrogen production. During Hydrotharmal pretreatment (HTP) maximum biohydrogen was examined when HTP done for 90 minutes. Total 4 runs were performed from raw corn stover to pretreated FRs and 92ml/g biohydrogen was produced.