Refractive error is one of the common eye diseases in children. Since children are highly regulated, ciliary muscle paralyzing agents are used to eliminate the effects of regulation in order to accurately examine the actual refractive error. The main difference is that the onset and recovery time of ciliary muscle paralysis and the depth of ciliary muscle paralysis are different. The effect of atropine as a reliable ciliary muscle paralyzing agent for children’s optometry is certain, and it has long been the routine to use atropine for children under 12 years old for dilated optometry, but due to its slow action and long duration, it often takes 2 to 3 weeks to recover, which affects children’s learning and outdoor activities, thus limiting the use of school-age children during school hours and bringing contradiction to the diagnosis and treatment of refractive error in children and school. Therefore, the search for an effective alternative drug has become necessary. Although compound tropicamide has the advantages of rapid onset of action, short duration of action, and low side effects, its ciliary muscle paralyzing effect is relatively small, there will be residual regulation, and it is a non-complete ciliary muscle paralyzing agent. Cyclopentetolide hydrochloride (trade name: Safeguard) is a new type of pupil dilating and ciliary muscle paralyzing agent. It can antagonize the excitatory effect of the iris sphincter and ciliary body ciliary muscle on cholinergic drugs, resulting in pupil dilatation and ciliary muscle paralysis, etc. It is a short-acting ciliary muscle paralyzing agent, and is the drug of choice for ophthalmic examinations abroad, and is widely used in refractive examinations, etc. It is now increasingly used in China. Studies have shown that the ciliary muscle paralysis effect of cyclopentetol ester hydrochloride eye drops is fast-acting and the ciliary muscle paralysis effect is stronger than that of tropicamide, without the inconvenience caused by the use of atropine for children’s life and study. Compared to atropine, the onset of action of Safije is fast, with the same value as atropine 3 times a day for 3 days; recovery in 24 hours, reducing the impact on the patient’s quality of life. The side effects are small and the safety is good. Specific use: Every 10 minutes before pupil dilatation, 3 dots in total, 1 hour after optometry. Most children recover after 1 day; some children who are more sensitive to the drug may need 2-3 days. In conclusion, cyclopentolate hydrochloride (Safeguard) is a safe and effective ciliary muscle paralyzing drug, its ciliary muscle paralyzing effect is fast-acting, the paralyzing effect is close to that of atropine, the duration of action does not exceed 72 hours, it can replace atropine for general refractive error non-strabismus children for optometry, it is recommended that the examination be performed about 1 hour after the drug is administered. For children with refractive errors with strabismus and other eye diseases caused by accommodation, we recommend to use atropine for optometry.