西安市的地质构造兼跨秦岭地槽褶皱带和华北地台两大单元。距今约1.3亿年前燕山运动时期产生横跨境内的秦岭北麓大断裂，自距今约300万年前第三纪晚期以来，大断裂以南秦岭地槽褶皱带新构造运动极为活跃，山体北仰南俯剧烈降升，造就秦岭山脉。与此同时，大断裂以北属于华北地台的渭河断陷继续沉降，在风积黄土覆盖和渭河冲积的共同作用下形成渭河平原。
[[File:西安市2.jpg|缩略图|西安市|[https://image.baidu.com/search/detail?ct=503316480&z=0&ipn=d&word=%E8%A5%BF%E5%AE%89%E5%B8%82&step_word=&hs=0&pn=13&spn=0&di=189640&pi=0&rn=1&tn=baiduimagedetail&is=0%2C0&istype=2&ie=utf-8&oe=utf-8&in=&cl=2&lm=-1&st=-1&cs=2343425925%2C162092258&os=3852635034%2C404211827&simid=3306139704%2C4020794604&adpicid=0&lpn=0&ln=1370&fr=&fmq=1569723331779_R&fm=result&ic=&s=undefined&hd=&latest=©right=&se=&sme=&tab=0&width=&height=&face=undefined&ist=&jit=&cg=&bdtype=0&oriquery=&objurl=http%3A%2F%2Fgss0.baidu.com%2F94o3dSag_xI4khGko9WTAnF6hhy%2Flvpics%2Fs%3D800%2Fsign%3Dde96ce05b41c8701d2b6bfe6177d9e6e%2F4e4a20a4462309f760b7ddf3750e0cf3d6cad673.jpg&fromurl=ippr_z2C%24qAzdH3FAzdH3Fooo_z%26e3Bp7xt_z%26e3Bv54_z%26e3BvgAzdH3Fetjok-nab088cn8n9bdb-nab088cn8n9bdbald9_z%26e3Bip4s&gsm=&rpstart=0&rpnum=0&islist=&querylist=&force=undefined 原图链接][https://image.baidu.com/search/detail?ct=503316480&z=0&ipn=d&word=%E8%A5%BF%E5%AE%89%E5%B8%82&step_word=&hs=0&pn=13&spn=0&di=189640&pi=0&rn=1&tn=baiduimagedetail&is=0%2C0&istype=2&ie=utf-8&oe=utf-8&in=&cl=2&lm=-1&st=-1&cs=2343425925%2C162092258&os=3852635034%2C404211827&simid=3306139704%2C4020794604&adpicid=0&lpn=0&ln=1370&fr=&fmq=1569723331779_R&fm=result&ic=&s=undefined&hd=&latest=©right=&se=&sme=&tab=0&width=&height=&face=undefined&ist=&jit=&cg=&bdtype=0&oriquery=&objurl=http%3A%2F%2Fgss0.baidu.com%2F94o3dSag_xI4khGko9WTAnF6hhy%2Flvpics%2Fs%3D800%2Fsign%3Dde96ce05b41c8701d2b6bfe6177d9e6e%2F4e4a20a4462309f760b7ddf3750e0cf3d6cad673.jpg&fromurl=ippr_z2C%24qAzdH3FAzdH3Fooo_z%26e3Bp7xt_z%26e3Bv54_z%26e3BvgAzdH3Fetjok-nab088cn8n9bdb-nab088cn8n9bdbald9_z%26e3Bip4s&gsm=&rpstart=0&rpnum=0&islist=&querylist=&force=undefined 来自 百度网 的图片]]]
西安市境内海拔高度差异悬殊位居全国各城市之冠。巍峨峻峭、群峰竞秀的秦岭山地与坦荡舒展、平畴沃野的渭河平原界线分明，构成西安市的地貌主体。秦岭山脉主脊海拔2000米～2800米，其中西南端太白山峰巅海拔3867米，是大陆中部最高山峰。渭河平原海拔400米～700米，其中东北端渭河河床最低处海拔345米。西安城区便建立在渭河平原的二级阶地上。
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