IO Cnc was classified to be a new G-type (G0) W UMa-type eclipsing binary system. Our first multicolor photometric solutions show that IO Cnc is a new W-subtype shallow contact binary with a fill-out factor of f = 16.1% and a low mass ratio of q = 3.12 (or 1/q = 0.32). During orbital period investigations, a cyclic variation and a downward parabolic variation with a rate of (−1.28 0.43) 10⁻⁷ d yr⁻¹ was discovered in the observed–calculated (O − C) curve. The cyclic variation was analyzed by the light travel time effect (LTTE) via a potential red dwarf companion star, an orbital semi-major axis shorter than 4.88 0.82 AU was obtained. Finally, we collect physical parameters of a sample of 50 G-type shallow contact binaries (f ≤ 20%), it is suggested that most of the G-type shallow contact binaries are undergoing a long-term and periodic orbital period changes, especially more systems show long-term decreases. The long-term orbital period decrease indicates that IO Cnc is in a mass transferring from the more massive component to the less massive one. With the long-term decrease of the orbital period, this shallow contact binary will evolve into a deeper contact one.

IO Cnc被归类为新的G型（G0）W UMa型食双星系统。我们的第一个多色光度计解决方案表明，IO Cnc 是一种新的 W 亚型浅接触二元，填充因子为f = 16.1%，质量比低为q = 3.12（或 1/ q = 0.32）。在轨道周期的调查，周期性变化，并用（-1.28 0.43）10的速率向下的抛物线变化^-7 d年^-1中所观察到的计算（发现ø - Ç） 曲线。通过潜在红矮星伴星的光旅行时效应（LTTE）分析了周期性变化，获得了短于4.88 0.82 AU的轨道半长轴。最后，我们收集了 50 个 G 型浅接触双星样本（f ≤ 20%）的物理参数，表明大部分 G 型浅接触双星正在经历长期和周期性的轨道周期变化，特别是更多的系统显示出长期下降。长期轨道周期的减少表明 IO Cnc 处于从质量较大的组件向质量较小的组件转移的质量中。随着轨道周期的长期减少，这种浅接触双星将演化为更深接触双星。