A microneedle using a biodegradable metal is represented by Chemical Formula 1 and is absorbed and degraded after subcutaneous or epithelial insertion to thus release metal ions and degradation products into the body. In Chemical Formula 1, a, b, and c represent wt % of respective ingredients, a+b+c=100 wt %, a or b has the highest value in the range of 0≤a≤100, 0≤b≤100, and 0≤c≤10, and X is one or more selected from the group consisting of Ca, Fe, Mn, Si, Na, Zr, Ce, and P.