Since TiO2 nanotube array feature in large specific surface area, strong adsorption capacity and high electron mobility, it has wide application prospect in fields including photocatalytic degradation of organic pollutants, dye sensitized solar cell, photolysis hydrogen production from water and gas sensitive components. It has become a research hotspot nowadays. Common preparation methods and preparation principles of TiO2 nanotube array were reviewed, advantages and disadvantages of these methods were also analyzed. Due to wide band gap, the light absorption wavelength of TiO2 was mainly in ultraviolet region, narrow photoresponse scope led to low utilization rate of visible light. Reducing the band gap of TiO2 and inhibiting recombination of photo-generated electron-hole pairs have become the focus of modification research aiming to improve the photocatalytic efficiency and utilization rate of solar energy of TiO2 nanotube arrays. Research progress on improving photocatalytic efficiency of TiO2 nanotube arrays by slowing down the recombination of photo-generated electron–hole pairs or making the red-shift of absorption edge, which resulted from the introduction of impurities or defects by doping metal or non-metal ions, deposition of noble metals and semiconductor nanoparticle modification, was also emphasized. Moreover, the future research focus and areas of TiO2 nanotube arrays regarding preparation, modification and application were pointed out.