Neutral kaons at KLOE

Neutral kaons provide one of the most sensitive systems to CP and CPT violation. Recent results on neutral kaons obtained by the KLOE experiment operating at the DAΦNE e+e− collider are presented. They include: the first observation of the quantum interference in the channel ϕ→KSKL→π+π−π+π−, the measurements of the main KL branching ratios, lifetime and form factor and the measurement of the semileptonic KS branching ratio. The latter are used for the determination of Vus. A direct search of the CP violating KS→π0π0π0 decay, a preliminary study of the KS→π0π+π− decay and the measurement of the branching ratio of the CP violating KL→π+π− decay are also presented.