Microalgae cultivation in wastewater is a greener approach to bioremediate the textile wastwater and biodiesel production. In this study, Chlorella vulgaris (C. vulgaris) was cultivated to investigate the bioremediation of TWW, biodiesel production, and feasibility of autotrophic and mixotrophic modes for the growth of microalgae. BG11 medium was used as a control to cultivate microalgae under autotrophic mode; meanwhile, methylene blue (MB) containing synthetic textile wastewater (TWW) as a diluted (50%) and undiluted TWW were used under mixotrophic mode. The optical density of C. vulgaris, MB decolorization (%), and removal of COD, N-NO₃, and PO₄ (%) were determined during the cultivation period. The maximum optical density of cells was found 1.62 in diluted TWW medium as compared to undiluted TWW (0.89) and BG11 (1.56) mediums. The highest MB decolorization of 99.7% was observed in diluted TWW as compared to 98.5% in undiluted TWW. Similarly, the highest removal (%) of COD, N-NO₃, and PO₄ were achieved 99.7, 95.7`, and 96.3%, respectively, for diluted TWW, followed by BG11 medium (COD = 94.4%, N-NO₃ = 92.9%, and PO₄ = 93.1%) and undiluted TWW (COD = 76.3%, N-NO₃ = 83.9%, and PO₄ = 85.6%). In addition, the highest lipid content was recorded in the diluted TWW medium (31.65 mg/L) than undiluted TWW medium (26.07 mg/L). Major fatty acid methyl ester (FAME) were palmitic acid (C16:0) and linolenoic acid (C18:3), which are suitable for biodiesel. The FAME profile showed that extracted lipids from microalgae are suitable for biodiesel production. Thus, it indicates that the integration of microalgae cultivation in textile wastewater with or without the addition of media provides as an alternative and sustainable solution for the bioremediation of TWW and biodiesel production.