Three dimensional (3D) complex microcrystal chains of SnO2 have been fabricated by simple carbothermal reduction based vapour deposition method. The structural and optical properties of the as-synthesized materials were well characterized by field emission scanning electron microscopy (FESEM) with energy dispersive X-ray spectroscopy, X-ray diffraction (XRD), Raman spectroscopy and photoluminescence spectroscopy. FESEM studies revealed the formation of 3D complex chains of microcrystals of SnO2 of varying shape and size. The SnO2 microcrystals have been found to be inter-connected through oriented attachment, leading to the formation of 3D complex chains of microcrystals. XRD studies showed the presence of SnO2 and Sn in the synthesized material. Photoluminescence studies on SnO2 microcrystal chains revealed peaks at 361, 407, 438 and 465 nm. A tentative mechanism of formation of the 3D complex chains of SnO2 microcrystals is proposed. These SnO2 microcrystal chains have potential applications as building blocks in novel functional devices.