In the present paper, a systematic study on the structural, linear and nonlinear optical properties of Zn1-xTixO (0 <= x <= 0.050) thin films is documented. The thin films are grown onto fused silica substrate via pulsed laser deposition technique employing 2nd harmonic of a Q-switched Nd:YAG laser (532 nm, lOns, 10 Hz). The crystallinity of the film is observed to be increased initially up-to x = 0.02 and then decreased for higher values of x. A small variation in band gap energy is observed in the Zn1-xTixO thin films with x which is mainly due to the Burstein Moss effect followed by the weak quantum confinement effect. The third order optical nonlinearities in the films are experimentally recorded using modified z-scan technique under cw He:Ne laser (lambda = 632.8 nm) illumination. The nonlinear optical coefficients; beta and n(2), are observed to be in the range of 1.1-6.0 cm/W and (1.0-4.1) x 10(-4) cm(2)/W, respectively. The maximum value of beta (6.0 cm/W) and n(2) (4.1 cm(2)/W) are observed in the Zn1-xTixO film having x = 0.02. These studies suggest that an optimum concentration of Ti content in ZnO is required for the enhancement in nonlinear optical behavior.