The VRI passbands light curves of V344 Lac were presented and analyzed by using the latest version of the W-D code .
The observed spectrum reveals that V344 Lac is not an A3 type but would be a later F type star according to the yielded temperature .
The results of solution show that V344 Lac is an A-subtype contact binary , with a mediate photometric mass ratio of 0.387 \pm 0.003 and a mediate contact factor of 44.6 \pm 3.0 % .
Based on the parallax given by Gaia , the parameters of the components are estimated as : M _ { 1 } = 1.16 { M _ { \odot } } , M _ { 2 } = 0.45 { M _ { \odot } } , R _ { 1 } = 1.31 { R _ { \odot } } , R _ { 2 } = 0.88 { R _ { \odot } } , L _ { 1 } = 2.512 { L _ { \odot } } , L _ { 2 } = 1.057 { L _ { \odot } } .
The period investigation indicates that V344 Lac may have an eccentric orbital oscillation , with P _ { 3 } = 12.4 \pm 0.5 yr , A _ { 3 } = 0.0020 \pm 0.0002 d , and e = 0.38 \pm 0.16 .
Analysis shows such oscillation would be caused by a magnetic activity which can be explained by the Applegate mechanism .
Meanwhile , according to the value of l _ { 3 } and the estimated physical parameters of V344 Lac , the mass of the third companion may be 0.79 M _ { \odot } .
This third body could be a wide company .