Originally from Haiyu (now Changshu, Jiangsu), later moved to Jintan. His father Shangzhi and brother Changqi died in prison due to the Donglin Party incident. The Miao family was implicated in the Donglin Party, and after evading capture, they relocated to Jintan. Miao was known for his upright and bold character. He studied under Sima Dafu and associated with many renowned physicians.

He authored Shennong Bencao Jingshu in 3 volumes (1625), Xianxingzhai Yixue Guangbiji in 3 volumes (1622), and also wrote 續 Shennong Bencao Jingshu , 方藥宜忌考, 仲淳醫案, materia medica 單方

, among others. Xianxingzhai Yixue Guangbiji

was compiled by his disciple Ding Changru, known for its concise language and practical methods, covering internal, external, gynecological, and pediatric fields with unique insights. The three key methods for hematemesis are particularly valued by later generations and are still used clinically today. Miao deeply researched the processing of materia medica, noting the different effects of decoctions, powders, ointments, liquids, and pills. For example, some require soaking in wine to enhance their potency; others need to be finely chopped, boiled in wine, and sealed to gradually release their effects. Similarly, for pills, some use flour paste to slow digestion and target the lower jiao

, while Pineilia and Arisaema use ginger juice and thin paste for easier digestion, and honeyed pills are used for slow digestion and circulation through meridians and collaterals, with wax pills being hard to digest, intended for delayed effect. He also believed that the properties of drugs change with the land, and thus, their use should be carefully considered. Miao criticized the fallacy of five circuits and six qi, stating that they are not medical texts for curing diseases and are of no benefit to treatment. The "Five Principles for Physicians" is an important document on medical ethics.