have a soft and ionic lattice. [3] Such ionic nature makes it possible to conduct anion exchange reactions from one kind of perovskite NCs, for example CsPbBr 3 , to another and thus achieve particles with different compositions such as CsPbCl 3 , CsPbI 3 , and their mixed-anion alloys, which is changing to accomplish for conventional semiconductor NCs. This enables bandgap tuning over the whole visible and even near-infrared spectral ranges while maintaining the size and morphology of the resulting NCs. [4] However, their ionic nature also makes the growth rates of perovskites extremely fast, with a completion of the NC growth ranging from less than a second to a couple of seconds. [5] The fast growth rate makes it difficult to control the final shape of perovskite NCs, [6] which will be elaborated upon in detail in this article further below. Useful properties of 1D semiconductor nanorods (NRs) including linearly polarized light emission, reduced lasing threshold, and improved charge transport [6] make them stand out from semiconductor NCs of other morphologies in a variety of applications such as liquid crystal displays (LCDs), lasers, solar cells and photocatalysis. [7] For example, aligned CdSe/CdS NRs incorporated in thin polymer films have been proposed as optical enhancement films to improve the brightness and broaden the color gamut of LCDs. [7b-d] In addition, CdSe/CdS, alloyed CdSe x S 1−x and CsPbBr 3 NRs have demonstrated a relatively low amplified spontaneous emission (ASE) threshold and a high net optical gain at a medium or low pump intensity, making them capable of producing lasing with low pumping thresholds. [7a,8] Furthermore, the 1D character of semiconductor NRs benefits efficient charge separation and provides specific spatial locations for selective deposition of other materials to realize 1D heterostructures, with prominent potentials in optoelectronics and photocatalysis. [9] Although there are a few documented attempts for the controlled chemical growth of perovskite NRs, [6b,7a,10] research into this area is still in its infancy. A high-degree of control during the synthesis of perovskite NRs in terms of size, aspect ratio, and performance, is not yet been fully realized. It is desirable to develop facile, robust, and scalable synthetic strategies for the preparation of high-quality perovskite NRs, to enrich the existing knowledge of their growth mechanisms, and to improve their optical and electronic properties that underpin their future applications. Quasi-1D metal halide perovskite nanorods (NRs) are emerging as a type of materials with remarkable optical and electronic properties. Research into this field is rapidly expanding and growing in the past several years, with significant advances in both mechanistic studies of their growth and widespread possible applications. Here, the recent advances in 1D metal halide perovskite nanocrystals (NCs) are reviewed, with a particular emphasis on NRs. At first, the crystal structures of perovskites are elaborated, which is followed by a revi...